{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-115269", "assignerOrgId": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db", "state": "PUBLISHED", "assignerShortName": "EEF", "dateReserved": "2026-10-23T10:15:01.872Z", "datePublished": "2026-10-26T13:30:24.621Z", "dateUpdated": "2026-10-26T15:35:52.079Z"}, "containers": {"cna": {"affected": [{"collectionURL": "https://repo.hex.pm", "cpes": ["cpe:2.3:a:mtrudel:bandit:*:*:*:*:*:*:*:*"], "defaultStatus": "unaffected", "packageName": "bandit", "packageURL": "pkg:hex/bandit", "product": "bandit", "repo": "https://github.com/mtrudel/bandit", "vendor": "mtrudel", "versions": [{"lessThan": "1.14.0", "status": "affected", "version": "1.4.0", "versionType": "semver"}]}, {"collectionURL": "https://github.com", "cpes": ["cpe:2.3:a:mtrudel:bandit:*:*:*:*:*:*:*:*"], "defaultStatus": "unaffected", "packageName": "mtrudel/bandit", "packageURL": "pkg:github/mtrudel/bandit", "product": "bandit", "repo": "https://github.com/mtrudel/bandit", "vendor": "mtrudel", "versions": [{"lessThan": "220b9dfd27f9a21305be2afc75cbe585ddc24e7a", "status": "affected", "version": "fff06efe3be962b484bd4d3eb339372fda5a231f", "versionType": "git"}]}], "cpeApplicability": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:a:mtrudel:bandit:*:*:*:*:*:*:*:*", "versionEndExcluding": "1.14.0", "versionStartIncluding": "1.4.0", "vulnerable": true}], "negate": false, "operator": "OR"}], "operator": "AND"}], "credits": [{"lang": "en", "type": "analyst", "value": "Peter Ullrich"}, {"lang": "en", "type": "reporter", "value": "Daniel Coles"}, {"lang": "en", "type": "remediation developer", "value": "Mat Trudel"}, {"lang": "en", "type": "analyst", "value": "Jonatan M\u00e4nnchen / EEF"}], "dateAssigned": "2026-10-23T13:25:29.000Z", "descriptions": [{"lang": "en", "supportingMedia": [{"base64": false, "type": "text/html", "value": "<p>Allocation of Resources Without Limits or Throttling vulnerability in the HTTP/2 request body reader of mtrudel bandit allows an unauthenticated remote attacker to hold stream processes open indefinitely via WINDOW_UPDATE or empty SETTINGS frames sent while a Plug reads the request body.</p>\n<p><code>Bandit.HTTP2.Stream.do_read_data/4</code> in <code>lib/bandit/http2/stream.ex</code> waits for each frame with a fresh <code>read_timeout</code>. A stream WINDOW_UPDATE, or the zero-delta window update that every empty SETTINGS frame delivers to all streams, ends the wait without delivering any body data, and the loop starts a new full countdown. A client that sends one of these 9-byte frames before each countdown expires keeps <code>read_body</code> blocked, together with the stream process and whatever the application holds while reading, for as long as it likes.</p>\n<p>This issue affects bandit: from 1.4.0 before 1.14.0.</p>"}, {"base64": false, "type": "text/markdown", "value": "Allocation of Resources Without Limits or Throttling vulnerability in the HTTP/2 request body reader of mtrudel bandit allows an unauthenticated remote attacker to hold stream processes open indefinitely via WINDOW_UPDATE or empty SETTINGS frames sent while a Plug reads the request body.\n\n`Bandit.HTTP2.Stream.do_read_data/4` in `lib/bandit/http2/stream.ex` waits for each frame with a fresh `read_timeout`. A stream WINDOW_UPDATE, or the zero-delta window update that every empty SETTINGS frame delivers to all streams, ends the wait without delivering any body data, and the loop starts a new full countdown. A client that sends one of these 9-byte frames before each countdown expires keeps `read_body` blocked, together with the stream process and whatever the application holds while reading, for as long as it likes.\n\nThis issue affects bandit: from 1.4.0 before 1.14.0."}], "value": "Allocation of Resources Without Limits or Throttling vulnerability in the HTTP/2 request body reader of mtrudel bandit allows an unauthenticated remote attacker to hold stream processes open indefinitely via WINDOW_UPDATE or empty SETTINGS frames sent while a Plug reads the request body.\n\nBandit.HTTP2.Stream.do_read_data/4 in lib/bandit/http2/stream.ex waits for each frame with a fresh read_timeout. A stream WINDOW_UPDATE, or the zero-delta window update that every empty SETTINGS frame delivers to all streams, ends the wait without delivering any body data, and the loop starts a new full countdown. A client that sends one of these 9-byte frames before each countdown expires keeps read_body blocked, together with the stream process and whatever the application holds while reading, for as long as it likes.\n\nThis issue affects bandit: from 1.4.0 before 1.14.0."}], "impacts": [{"capecId": "CAPEC-469", "descriptions": [{"lang": "en", "supportingMedia": [{"base64": false, "type": "text/html", "value": "<p>An unauthenticated client can keep a Bandit HTTP/2 stream, and whatever its request handler holds while reading the body, occupied indefinitely for 9 bytes per <code>read_timeout</code>, and repeat this across many streams and connections. This affects any Bandit server with HTTP/2 enabled whose routes read request bodies, which <code>Plug.Parsers</code> does for POST, PUT and PATCH.</p>"}, {"base64": false, "type": "text/markdown", "value": "An unauthenticated client can keep a Bandit HTTP/2 stream, and whatever its request handler holds while reading the body, occupied indefinitely for 9 bytes per `read_timeout`, and repeat this across many streams and connections. This affects any Bandit server with HTTP/2 enabled whose routes read request bodies, which `Plug.Parsers` does for POST, PUT and PATCH."}], "value": "An unauthenticated client can keep a Bandit HTTP/2 stream, and whatever its request handler holds while reading the body, occupied indefinitely for 9 bytes per read_timeout, and repeat this across many streams and connections. This affects any Bandit server with HTTP/2 enabled whose routes read request bodies, which Plug.Parsers does for POST, PUT and PATCH."}]}], "metrics": [{"cvssV4_0": {"Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "LOW", "attackRequirements": "NONE", "attackVector": "NETWORK", "baseScore": 8.7, "baseSeverity": "HIGH", "privilegesRequired": "NONE", "providerUrgency": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "userInteraction": "NONE", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N", "version": "4.0", "vulnAvailabilityImpact": "HIGH", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "NONE", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "format": "CVSS", "scenarios": [{"lang": "en", "value": "GENERAL"}]}], "problemTypes": [{"descriptions": [{"cweId": "CWE-835", "description": "CWE-835 Loop with Unreachable Exit Condition ('Infinite Loop')", "lang": "en", "type": "CWE"}]}, {"descriptions": [{"cweId": "CWE-770", "description": "CWE-770 Allocation of Resources Without Limits or Throttling", "lang": "en", "type": "CWE"}]}], "providerMetadata": {"orgId": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db", "shortName": "EEF", "dateUpdated": "2026-10-26T13:30:24.621Z"}, "references": [{"name": "HTTP/2 WINDOW_UPDATE and SETTINGS frames reset the request body read timeout in Bandit", "tags": ["vendor-advisory", "related"], "url": "https://github.com/mtrudel/bandit/security/advisories/GHSA-p2qv-vx88-385x"}, {"name": "EEF CNA record for CVE-2026-115269", "tags": ["related"], "url": "https://cna.erlef.org/cves/CVE-2026-115269.html"}, {"name": "OSV record EEF-CVE-2026-115269", "tags": ["related"], "url": "https://osv.dev/vulnerability/EEF-CVE-2026-115269"}, {"name": "Introducing commit fff06ef in mtrudel/bandit", "tags": ["related"], "url": "https://github.com/mtrudel/bandit/commit/fff06efe3be962b484bd4d3eb339372fda5a231f"}, {"name": "Fix commit 220b9df in mtrudel/bandit", "tags": ["patch"], "url": "https://github.com/mtrudel/bandit/commit/220b9dfd27f9a21305be2afc75cbe585ddc24e7a"}], "source": {"discovery": "UNKNOWN"}, "title": "HTTP/2 WINDOW_UPDATE and SETTINGS frames reset the request body read timeout in Bandit", "workarounds": [{"lang": "en", "supportingMedia": [{"base64": false, "type": "text/html", "value": "<p>Disable HTTP/2 with <code>http_2_options: [enabled: false]</code>, so that the vulnerable read path never runs.</p>"}, {"base64": false, "type": "text/markdown", "value": "Disable HTTP/2 with `http_2_options: [enabled: false]`, so that the vulnerable read path never runs."}], "value": "Disable HTTP/2 with http_2_options: [enabled: false], so that the vulnerable read path never runs."}], "x_proofOfConcept": [{"lang": "en", "supportingMedia": [{"base64": false, "type": "text/html", "value": "<ol>\n<li>Run Bandit with a Plug that calls <code>Plug.Conn.read_body/2</code>.</li>\n<li>Open an HTTP/2 connection and send HEADERS for <code>POST /</code> on stream 1 without END_STREAM.</li>\n<li>Every 10 seconds, send a WINDOW_UPDATE on stream 1 with an increment of 1.</li>\n<li>The stream stays open for 120 s, eight times the default 15 s <code>read_timeout</code>. Without the WINDOW_UPDATE frames, the server ends the read after about 15 s.</li>\n</ol>"}, {"base64": false, "type": "text/markdown", "value": "1. Run Bandit with a Plug that calls `Plug.Conn.read_body/2`.\n2. Open an HTTP/2 connection and send HEADERS for `POST /` on stream 1 without END_STREAM.\n3. Every 10 seconds, send a WINDOW_UPDATE on stream 1 with an increment of 1.\n4. The stream stays open for 120 s, eight times the default 15 s `read_timeout`. Without the WINDOW_UPDATE frames, the server ends the read after about 15 s."}], "value": "* Run Bandit with a Plug that calls Plug.Conn.read_body/2.\n* Open an HTTP/2 connection and send HEADERS for POST / on stream 1 without END_STREAM.\n* Every 10 seconds, send a WINDOW_UPDATE on stream 1 with an increment of 1.\n* The stream stays open for 120 s, eight times the default 15 s read_timeout. Without the WINDOW_UPDATE frames, the server ends the read after about 15 s."}], "x_technicalAnalysis": [{"lang": "en", "supportingMedia": [{"base64": false, "type": "text/html", "value": "<p><strong>1. Per-receive timeout.</strong> <code>Bandit.HTTP2.Stream.read_data/2</code> passes a flat <code>read_timeout</code> (default 15,000 ms) to <code>do_read_data/4</code>, which blocks in <code>do_recv/2</code>'s <code>receive ... after timeout</code>.</p>\n<p><strong>2. Non-progress frames end the wait.</strong> A stream WINDOW_UPDATE, delivered through <code>Bandit.HTTP2.Connection.handle_frame/3</code>, or an empty SETTINGS frame, which delivers a zero-delta window update to every stream, is matched inside that <code>receive</code>. <code>do_recv_send_window_update/2</code> returns a bare <code>%Stream{}</code>, and <code>do_read_data/4</code> recurses with the identical <code>timeout</code>, restarting the countdown.</p>\n<p><strong>3. Nothing else bounds the read.</strong> The transport read timeout fires only when no bytes arrive, <code>max_bytes</code> is decremented only by DATA frames, and neither WINDOW_UPDATE nor SETTINGS frames are rate limited. The send path in <code>do_send_data/4</code> uses a progress-based deadline; the read path does not.</p>"}, {"base64": false, "type": "text/markdown", "value": "**1. Per-receive timeout.** `Bandit.HTTP2.Stream.read_data/2` passes a flat `read_timeout` (default 15,000 ms) to `do_read_data/4`, which blocks in `do_recv/2`'s `receive ... after timeout`.\n\n**2. Non-progress frames end the wait.** A stream WINDOW_UPDATE, delivered through `Bandit.HTTP2.Connection.handle_frame/3`, or an empty SETTINGS frame, which delivers a zero-delta window update to every stream, is matched inside that `receive`. `do_recv_send_window_update/2` returns a bare `%Stream{}`, and `do_read_data/4` recurses with the identical `timeout`, restarting the countdown.\n\n**3. Nothing else bounds the read.** The transport read timeout fires only when no bytes arrive, `max_bytes` is decremented only by DATA frames, and neither WINDOW_UPDATE nor SETTINGS frames are rate limited. The send path in `do_send_data/4` uses a progress-based deadline; the read path does not."}], "value": "1. Per-receive timeout. Bandit.HTTP2.Stream.read_data/2 passes a flat read_timeout (default 15,000 ms) to do_read_data/4, which blocks in do_recv/2's receive ... after timeout.\n\n2. Non-progress frames end the wait. A stream WINDOW_UPDATE, delivered through Bandit.HTTP2.Connection.handle_frame/3, or an empty SETTINGS frame, which delivers a zero-delta window update to every stream, is matched inside that receive. do_recv_send_window_update/2 returns a bare %Stream{}, and do_read_data/4 recurses with the identical timeout, restarting the countdown.\n\n3. Nothing else bounds the read. The transport read timeout fires only when no bytes arrive, max_bytes is decremented only by DATA frames, and neither WINDOW_UPDATE nor SETTINGS frames are rate limited. The send path in do_send_data/4 uses a progress-based deadline; the read path does not."}]}, "adp": [{"metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2026-115269", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "yes"}, {"Technical Impact": "partial"}], "version": "2.0.3", "timestamp": "2026-10-26T15:02:19.174445Z"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-10-26T15:35:52.079Z"}}]}}

{"dataType": "CVE_RECORD", "containers": {"adp": [{"title": "CISA ADP Vulnrichment", "metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2026-115269", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "yes"}, {"Technical Impact": "partial"}], "version": "2.0.3", "timestamp": "2026-10-26T15:02:19.174445Z"}}}], "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-10-26T15:33:07.848Z"}}], "cna": {"title": "HTTP/2 WINDOW_UPDATE and SETTINGS frames reset the request body read timeout in Bandit", "source": {"discovery": "UNKNOWN"}, "credits": [{"lang": "en", "type": "analyst", "value": "Peter Ullrich"}, {"lang": "en", "type": "reporter", "value": "Daniel Coles"}, {"lang": "en", "type": "remediation developer", "value": "Mat Trudel"}, {"lang": "en", "type": "analyst", "value": "Jonatan M\u00e4nnchen / EEF"}], "impacts": [{"capecId": "CAPEC-469", "descriptions": [{"lang": "en", "value": "An unauthenticated client can keep a Bandit HTTP/2 stream, and whatever its request handler holds while reading the body, occupied indefinitely for 9 bytes per read_timeout, and repeat this across many streams and connections. This affects any Bandit server with HTTP/2 enabled whose routes read request bodies, which Plug.Parsers does for POST, PUT and PATCH.", "supportingMedia": [{"type": "text/html", "value": "<p>An unauthenticated client can keep a Bandit HTTP/2 stream, and whatever its request handler holds while reading the body, occupied indefinitely for 9 bytes per <code>read_timeout</code>, and repeat this across many streams and connections. This affects any Bandit server with HTTP/2 enabled whose routes read request bodies, which <code>Plug.Parsers</code> does for POST, PUT and PATCH.</p>", "base64": false}, {"type": "text/markdown", "value": "An unauthenticated client can keep a Bandit HTTP/2 stream, and whatever its request handler holds while reading the body, occupied indefinitely for 9 bytes per `read_timeout`, and repeat this across many streams and connections. This affects any Bandit server with HTTP/2 enabled whose routes read request bodies, which `Plug.Parsers` does for POST, PUT and PATCH.", "base64": false}]}]}], "metrics": [{"format": "CVSS", "cvssV4_0": {"Safety": "NOT_DEFINED", "version": "4.0", "Recovery": "NOT_DEFINED", "baseScore": 8.7, "Automatable": "NOT_DEFINED", "attackVector": "NETWORK", "baseSeverity": "HIGH", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N", "providerUrgency": "NOT_DEFINED", "userInteraction": "NONE", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "subIntegrityImpact": "NONE", "vulnIntegrityImpact": "NONE", "subAvailabilityImpact": "NONE", "vulnAvailabilityImpact": "HIGH", "subConfidentialityImpact": "NONE", "vulnConfidentialityImpact": "NONE", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "scenarios": [{"lang": "en", "value": "GENERAL"}]}], "affected": [{"cpes": ["cpe:2.3:a:mtrudel:bandit:*:*:*:*:*:*:*:*"], "repo": "https://github.com/mtrudel/bandit", "vendor": "mtrudel", "product": "bandit", "versions": [{"status": "affected", "version": "1.4.0", "lessThan": "1.14.0", "versionType": "semver"}], "packageURL": "pkg:hex/bandit", "packageName": "bandit", "collectionURL": "https://repo.hex.pm", "defaultStatus": "unaffected"}, {"cpes": ["cpe:2.3:a:mtrudel:bandit:*:*:*:*:*:*:*:*"], "repo": "https://github.com/mtrudel/bandit", "vendor": "mtrudel", "product": "bandit", "versions": [{"status": "affected", "version": "fff06efe3be962b484bd4d3eb339372fda5a231f", "lessThan": "220b9dfd27f9a21305be2afc75cbe585ddc24e7a", "versionType": "git"}], "packageURL": "pkg:github/mtrudel/bandit", "packageName": "mtrudel/bandit", "collectionURL": "https://github.com", "defaultStatus": "unaffected"}], "references": [{"url": "https://github.com/mtrudel/bandit/security/advisories/GHSA-p2qv-vx88-385x", "name": "HTTP/2 WINDOW_UPDATE and SETTINGS frames reset the request body read timeout in Bandit", "tags": ["vendor-advisory", "related"]}, {"url": "https://cna.erlef.org/cves/CVE-2026-115269.html", "name": "EEF CNA record for CVE-2026-115269", "tags": ["related"]}, {"url": "https://osv.dev/vulnerability/EEF-CVE-2026-115269", "name": "OSV record EEF-CVE-2026-115269", "tags": ["related"]}, {"url": "https://github.com/mtrudel/bandit/commit/fff06efe3be962b484bd4d3eb339372fda5a231f", "name": "Introducing commit fff06ef in mtrudel/bandit", "tags": ["related"]}, {"url": "https://github.com/mtrudel/bandit/commit/220b9dfd27f9a21305be2afc75cbe585ddc24e7a", "name": "Fix commit 220b9df in mtrudel/bandit", "tags": ["patch"]}], "workarounds": [{"lang": "en", "value": "Disable HTTP/2 with http_2_options: [enabled: false], so that the vulnerable read path never runs.", "supportingMedia": [{"type": "text/html", "value": "<p>Disable HTTP/2 with <code>http_2_options: [enabled: false]</code>, so that the vulnerable read path never runs.</p>", "base64": false}, {"type": "text/markdown", "value": "Disable HTTP/2 with `http_2_options: [enabled: false]`, so that the vulnerable read path never runs.", "base64": false}]}], "dateAssigned": "2026-10-23T13:25:29.000Z", "descriptions": [{"lang": "en", "value": "Allocation of Resources Without Limits or Throttling vulnerability in the HTTP/2 request body reader of mtrudel bandit allows an unauthenticated remote attacker to hold stream processes open indefinitely via WINDOW_UPDATE or empty SETTINGS frames sent while a Plug reads the request body.\n\nBandit.HTTP2.Stream.do_read_data/4 in lib/bandit/http2/stream.ex waits for each frame with a fresh read_timeout. A stream WINDOW_UPDATE, or the zero-delta window update that every empty SETTINGS frame delivers to all streams, ends the wait without delivering any body data, and the loop starts a new full countdown. A client that sends one of these 9-byte frames before each countdown expires keeps read_body blocked, together with the stream process and whatever the application holds while reading, for as long as it likes.\n\nThis issue affects bandit: from 1.4.0 before 1.14.0.", "supportingMedia": [{"type": "text/html", "value": "<p>Allocation of Resources Without Limits or Throttling vulnerability in the HTTP/2 request body reader of mtrudel bandit allows an unauthenticated remote attacker to hold stream processes open indefinitely via WINDOW_UPDATE or empty SETTINGS frames sent while a Plug reads the request body.</p>\n<p><code>Bandit.HTTP2.Stream.do_read_data/4</code> in <code>lib/bandit/http2/stream.ex</code> waits for each frame with a fresh <code>read_timeout</code>. A stream WINDOW_UPDATE, or the zero-delta window update that every empty SETTINGS frame delivers to all streams, ends the wait without delivering any body data, and the loop starts a new full countdown. A client that sends one of these 9-byte frames before each countdown expires keeps <code>read_body</code> blocked, together with the stream process and whatever the application holds while reading, for as long as it likes.</p>\n<p>This issue affects bandit: from 1.4.0 before 1.14.0.</p>", "base64": false}, {"type": "text/markdown", "value": "Allocation of Resources Without Limits or Throttling vulnerability in the HTTP/2 request body reader of mtrudel bandit allows an unauthenticated remote attacker to hold stream processes open indefinitely via WINDOW_UPDATE or empty SETTINGS frames sent while a Plug reads the request body.\n\n`Bandit.HTTP2.Stream.do_read_data/4` in `lib/bandit/http2/stream.ex` waits for each frame with a fresh `read_timeout`. A stream WINDOW_UPDATE, or the zero-delta window update that every empty SETTINGS frame delivers to all streams, ends the wait without delivering any body data, and the loop starts a new full countdown. A client that sends one of these 9-byte frames before each countdown expires keeps `read_body` blocked, together with the stream process and whatever the application holds while reading, for as long as it likes.\n\nThis issue affects bandit: from 1.4.0 before 1.14.0.", "base64": false}]}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-835", "description": "CWE-835 Loop with Unreachable Exit Condition ('Infinite Loop')"}]}, {"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-770", "description": "CWE-770 Allocation of Resources Without Limits or Throttling"}]}], "cpeApplicability": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:mtrudel:bandit:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "1.14.0", "versionStartIncluding": "1.4.0"}], "operator": "OR"}], "operator": "AND"}], "providerMetadata": {"orgId": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db", "shortName": "EEF", "dateUpdated": "2026-10-26T13:30:24.621Z"}, "x_proofOfConcept": [{"lang": "en", "value": "* Run Bandit with a Plug that calls Plug.Conn.read_body/2.\n* Open an HTTP/2 connection and send HEADERS for POST / on stream 1 without END_STREAM.\n* Every 10 seconds, send a WINDOW_UPDATE on stream 1 with an increment of 1.\n* The stream stays open for 120 s, eight times the default 15 s read_timeout. Without the WINDOW_UPDATE frames, the server ends the read after about 15 s.", "supportingMedia": [{"type": "text/html", "value": "<ol>\n<li>Run Bandit with a Plug that calls <code>Plug.Conn.read_body/2</code>.</li>\n<li>Open an HTTP/2 connection and send HEADERS for <code>POST /</code> on stream 1 without END_STREAM.</li>\n<li>Every 10 seconds, send a WINDOW_UPDATE on stream 1 with an increment of 1.</li>\n<li>The stream stays open for 120 s, eight times the default 15 s <code>read_timeout</code>. Without the WINDOW_UPDATE frames, the server ends the read after about 15 s.</li>\n</ol>", "base64": false}, {"type": "text/markdown", "value": "1. Run Bandit with a Plug that calls `Plug.Conn.read_body/2`.\n2. Open an HTTP/2 connection and send HEADERS for `POST /` on stream 1 without END_STREAM.\n3. Every 10 seconds, send a WINDOW_UPDATE on stream 1 with an increment of 1.\n4. The stream stays open for 120 s, eight times the default 15 s `read_timeout`. Without the WINDOW_UPDATE frames, the server ends the read after about 15 s.", "base64": false}]}], "x_technicalAnalysis": [{"lang": "en", "value": "1. Per-receive timeout. Bandit.HTTP2.Stream.read_data/2 passes a flat read_timeout (default 15,000 ms) to do_read_data/4, which blocks in do_recv/2's receive ... after timeout.\n\n2. Non-progress frames end the wait. A stream WINDOW_UPDATE, delivered through Bandit.HTTP2.Connection.handle_frame/3, or an empty SETTINGS frame, which delivers a zero-delta window update to every stream, is matched inside that receive. do_recv_send_window_update/2 returns a bare %Stream{}, and do_read_data/4 recurses with the identical timeout, restarting the countdown.\n\n3. Nothing else bounds the read. The transport read timeout fires only when no bytes arrive, max_bytes is decremented only by DATA frames, and neither WINDOW_UPDATE nor SETTINGS frames are rate limited. The send path in do_send_data/4 uses a progress-based deadline; the read path does not.", "supportingMedia": [{"type": "text/html", "value": "<p><strong>1. Per-receive timeout.</strong> <code>Bandit.HTTP2.Stream.read_data/2</code> passes a flat <code>read_timeout</code> (default 15,000 ms) to <code>do_read_data/4</code>, which blocks in <code>do_recv/2</code>'s <code>receive ... after timeout</code>.</p>\n<p><strong>2. Non-progress frames end the wait.</strong> A stream WINDOW_UPDATE, delivered through <code>Bandit.HTTP2.Connection.handle_frame/3</code>, or an empty SETTINGS frame, which delivers a zero-delta window update to every stream, is matched inside that <code>receive</code>. <code>do_recv_send_window_update/2</code> returns a bare <code>%Stream{}</code>, and <code>do_read_data/4</code> recurses with the identical <code>timeout</code>, restarting the countdown.</p>\n<p><strong>3. Nothing else bounds the read.</strong> The transport read timeout fires only when no bytes arrive, <code>max_bytes</code> is decremented only by DATA frames, and neither WINDOW_UPDATE nor SETTINGS frames are rate limited. The send path in <code>do_send_data/4</code> uses a progress-based deadline; the read path does not.</p>", "base64": false}, {"type": "text/markdown", "value": "**1. Per-receive timeout.** `Bandit.HTTP2.Stream.read_data/2` passes a flat `read_timeout` (default 15,000 ms) to `do_read_data/4`, which blocks in `do_recv/2`'s `receive ... after timeout`.\n\n**2. Non-progress frames end the wait.** A stream WINDOW_UPDATE, delivered through `Bandit.HTTP2.Connection.handle_frame/3`, or an empty SETTINGS frame, which delivers a zero-delta window update to every stream, is matched inside that `receive`. `do_recv_send_window_update/2` returns a bare `%Stream{}`, and `do_read_data/4` recurses with the identical `timeout`, restarting the countdown.\n\n**3. Nothing else bounds the read.** The transport read timeout fires only when no bytes arrive, `max_bytes` is decremented only by DATA frames, and neither WINDOW_UPDATE nor SETTINGS frames are rate limited. The send path in `do_send_data/4` uses a progress-based deadline; the read path does not.", "base64": false}]}]}}, "cveMetadata": {"cveId": "CVE-2026-115269", "state": "PUBLISHED", "dateUpdated": "2026-10-26T15:35:52.079Z", "dateReserved": "2026-10-23T10:15:01.872Z", "assignerOrgId": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db", "datePublished": "2026-10-26T13:30:24.621Z", "assignerShortName": "EEF"}, "dataVersion": "5.2"}

{"affected": [{"affectedData": [{"collectionURL": "https://repo.hex.pm", "cpes": ["cpe:2.3:a:mtrudel:bandit:*:*:*:*:*:*:*:*"], "defaultStatus": "unaffected", "packageName": "bandit", "packageURL": "pkg:hex/bandit", "product": "bandit", "repo": "https://github.com/mtrudel/bandit", "vendor": "mtrudel", "versions": [{"lessThan": "1.14.0", "status": "affected", "version": "1.4.0", "versionType": "semver"}]}, {"collectionURL": "https://github.com", "cpes": ["cpe:2.3:a:mtrudel:bandit:*:*:*:*:*:*:*:*"], "defaultStatus": "unaffected", "packageName": "mtrudel/bandit", "packageURL": "pkg:github/mtrudel/bandit", "product": "bandit", "repo": "https://github.com/mtrudel/bandit", "vendor": "mtrudel", "versions": [{"lessThan": "220b9dfd27f9a21305be2afc75cbe585ddc24e7a", "status": "affected", "version": "fff06efe3be962b484bd4d3eb339372fda5a231f", "versionType": "git"}]}], "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Allocation of Resources Without Limits or Throttling vulnerability in the HTTP/2 request body reader of mtrudel bandit allows an unauthenticated remote attacker to hold stream processes open indefinitely via WINDOW_UPDATE or empty SETTINGS frames sent while a Plug reads the request body.\n\nBandit.HTTP2.Stream.do_read_data/4 in lib/bandit/http2/stream.ex waits for each frame with a fresh read_timeout. A stream WINDOW_UPDATE, or the zero-delta window update that every empty SETTINGS frame delivers to all streams, ends the wait without delivering any body data, and the loop starts a new full countdown. A client that sends one of these 9-byte frames before each countdown expires keeps read_body blocked, together with the stream process and whatever the application holds while reading, for as long as it likes.\n\nThis issue affects bandit: from 1.4.0 before 1.14.0."}], "id": "CVE-2026-115269", "lastModified": "2026-10-26T16:17:17.123", "metrics": {"cvssMetricV40": [{"cvssData": {"Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "LOW", "attackRequirements": "NONE", "attackVector": "NETWORK", "availabilityRequirement": "NOT_DEFINED", "baseScore": 8.7, "baseSeverity": "HIGH", "confidentialityRequirement": "NOT_DEFINED", "exploitMaturity": "NOT_DEFINED", "integrityRequirement": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "privilegesRequired": "NONE", "providerUrgency": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "userInteraction": "NONE", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X", "version": "4.0", "vulnAvailabilityImpact": "HIGH", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "NONE", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-115269", "options": [{"exploitation": "none"}, {"automatable": "yes"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-10-26T15:02:19.174445Z", "version": "2.0.3"}}]}, "published": "2026-10-26T14:16:31.290", "references": [{"source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db", "url": "https://cna.erlef.org/cves/CVE-2026-115269.html"}, {"source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db", "url": "https://github.com/mtrudel/bandit/commit/220b9dfd27f9a21305be2afc75cbe585ddc24e7a"}, {"source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db", "url": "https://github.com/mtrudel/bandit/commit/fff06efe3be962b484bd4d3eb339372fda5a231f"}, {"source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db", "url": "https://github.com/mtrudel/bandit/security/advisories/GHSA-p2qv-vx88-385x"}, {"source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db", "url": "https://osv.dev/vulnerability/EEF-CVE-2026-115269"}], "sourceIdentifier": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-770"}, {"lang": "en", "value": "CWE-835"}], "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db", "type": "Secondary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[1.4.0,1.14.0)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[fff06efe3be962b484bd4d3eb339372fda5a231f,220b9dfd27f9a21305be2afc75cbe585ddc24e7a)"}}], "enrichment": {"confidence": 95.0, "confidence_source": "inferred", "scores": [{"score": 95.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "bandit", "source": "cna", "vendor": "mtrudel"}, "product": "bandit", "vendor": "mtrudel"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[fff06efe3be962b484bd4d3eb339372fda5a231f,220b9dfd27f9a21305be2afc75cbe585ddc24e7a)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "bandit", "source": "cna", "vendor": "mtrudel"}, "product": "bandit", "vendor": "mtrudel"}], "created": "2026-10-26T16:15:14.282711+00:00", "updated": "2026-10-26T16:15:14.282740+00:00", "vendors": ["mtrudel", "mtrudel$PRODUCT$bandit"]}