Description
In the Linux kernel, the following vulnerability has been resolved:
sctp: validate chunk length in the inqueue parser
SCTP chunks always include a four-byte generic header, but
sctp_inq_pop() currently accepts shorter declared lengths. A zero-length
chunk leaves chunk_end at the current header.
When ASCONF is covered by the association's SCTP-AUTH policy,
sctp_assoc_bh_rcv() can continue before the state machine performs its
normal chunk-length check. sctp_inq_pop() then returns the same malformed
chunk repeatedly and the receive softirq can lock up.
A remote SCTP peer can trigger this after establishing an association on
a kernel built with CONFIG_IP_SCTP and configured with
net.sctp.addip_enable=1 and net.sctp.auth_enable=1. The reproducer did
not require application credentials, a shared SCTP AUTH key, or
net.sctp.addip_noauth_enable=1.
On commit f967455fb2a5 ("seg6: reset IP6CB after IPv6 decapsulation"),
one zero-length ASCONF caused repeated
watchdog soft-lockup reports in a two-vCPU KVM guest. All 3 pre-trigger
health probes succeeded, while 36 of 37 post-trigger probes failed. With
this change, all 37 post-trigger probes succeeded and no equivalent
soft-lockup signature appeared.
Reject chunks shorter than the generic SCTP header at the shared inqueue
parser boundary. Mark the packet for discard before either caller can
continue processing it, while preserving the four-byte generic minimum.
Declared-length 1 through 4 controls and kernel-generated ASCONF traffic
remained healthy. The patched sctp_hello selftest passed for IPv4 and
IPv6.
The complete private reproducer and validation evidence are available
directly to maintainers on request.
sctp: validate chunk length in the inqueue parser
SCTP chunks always include a four-byte generic header, but
sctp_inq_pop() currently accepts shorter declared lengths. A zero-length
chunk leaves chunk_end at the current header.
When ASCONF is covered by the association's SCTP-AUTH policy,
sctp_assoc_bh_rcv() can continue before the state machine performs its
normal chunk-length check. sctp_inq_pop() then returns the same malformed
chunk repeatedly and the receive softirq can lock up.
A remote SCTP peer can trigger this after establishing an association on
a kernel built with CONFIG_IP_SCTP and configured with
net.sctp.addip_enable=1 and net.sctp.auth_enable=1. The reproducer did
not require application credentials, a shared SCTP AUTH key, or
net.sctp.addip_noauth_enable=1.
On commit f967455fb2a5 ("seg6: reset IP6CB after IPv6 decapsulation"),
one zero-length ASCONF caused repeated
watchdog soft-lockup reports in a two-vCPU KVM guest. All 3 pre-trigger
health probes succeeded, while 36 of 37 post-trigger probes failed. With
this change, all 37 post-trigger probes succeeded and no equivalent
soft-lockup signature appeared.
Reject chunks shorter than the generic SCTP header at the shared inqueue
parser boundary. Mark the packet for discard before either caller can
continue processing it, while preserving the four-byte generic minimum.
Declared-length 1 through 4 controls and kernel-generated ASCONF traffic
remained healthy. The patched sctp_hello selftest passed for IPv4 and
IPv6.
The complete private reproducer and validation evidence are available
directly to maintainers on request.
Published:
2026-10-28
Score:
n/a
EPSS:
n/a
KEV:
No
Analysis
Analysis and contextual insights are available on OpenCVE Cloud.
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | ||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Linux | Linux | unaffected |
|
||||||||||||||||||
| Linux | Linux | affected |
|
No data.
No data.
No data available yet.
Remediation
No solution or workaround provided in the CVE record.
Additional remediation guidance may be available on OpenCVE Cloud.
Tracking
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Advisories
No advisories yet.
References
History
Wed, 28 Oct 2026 12:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Weaknesses | CWE-682 |
Wed, 28 Oct 2026 10:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: sctp: validate chunk length in the inqueue parser SCTP chunks always include a four-byte generic header, but sctp_inq_pop() currently accepts shorter declared lengths. A zero-length chunk leaves chunk_end at the current header. When ASCONF is covered by the association's SCTP-AUTH policy, sctp_assoc_bh_rcv() can continue before the state machine performs its normal chunk-length check. sctp_inq_pop() then returns the same malformed chunk repeatedly and the receive softirq can lock up. A remote SCTP peer can trigger this after establishing an association on a kernel built with CONFIG_IP_SCTP and configured with net.sctp.addip_enable=1 and net.sctp.auth_enable=1. The reproducer did not require application credentials, a shared SCTP AUTH key, or net.sctp.addip_noauth_enable=1. On commit f967455fb2a5 ("seg6: reset IP6CB after IPv6 decapsulation"), one zero-length ASCONF caused repeated watchdog soft-lockup reports in a two-vCPU KVM guest. All 3 pre-trigger health probes succeeded, while 36 of 37 post-trigger probes failed. With this change, all 37 post-trigger probes succeeded and no equivalent soft-lockup signature appeared. Reject chunks shorter than the generic SCTP header at the shared inqueue parser boundary. Mark the packet for discard before either caller can continue processing it, while preserving the four-byte generic minimum. Declared-length 1 through 4 controls and kernel-generated ASCONF traffic remained healthy. The patched sctp_hello selftest passed for IPv4 and IPv6. The complete private reproducer and validation evidence are available directly to maintainers on request. | |
| Title | sctp: validate chunk length in the inqueue parser | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
MITRE
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-10-28T10:34:42.229Z
Reserved: 2026-09-25T10:25:14.394Z
Link: CVE-2026-99128
Vulnrichment
No data.
NVD
Status : Received
Published: 2026-10-28T11:17:32.570
Modified: 2026-10-28T11:17:32.570
Link: CVE-2026-99128
Redhat
No data.
OpenCVE Enrichment
Updated: 2026-10-28T11:45:09Z
Weaknesses