Description
Cyrus SASL through 2.1.28 contains an authentication bypass vulnerability in the SRP server mechanism because srp_server_mech_step2 does not reject client public values A that are multiples of N. Unauthenticated network clients can send A equal to N to force a zero shared secret, authenticating as any existing user without the password and learning session keys.
Published: 2026-11-15
Score: 9.3 Critical
EPSS: n/a
KEV: No
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Remediation

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History

Sun, 15 Nov 2026 14:00:00 +0000

Type Values Removed Values Added
Description Cyrus SASL through 2.1.28 contains an authentication bypass vulnerability in the SRP server mechanism because srp_server_mech_step2 does not reject client public values A that are multiples of N. Unauthenticated network clients can send A equal to N to force a zero shared secret, authenticating as any existing user without the password and learning session keys.
Title Cyrus SASL through 2.1.28 SRP Authentication Bypass via plugins/srp.c
First Time appeared Cyrusimap
Cyrusimap cyrus-sasl
Weaknesses CWE-287
CPEs cpe:2.3:a:cyrusimap:cyrus-sasl:*:*:*:*:*:*:*:*
Vendors & Products Cyrusimap
Cyrusimap cyrus-sasl
References
Metrics cvssV3_1

{'score': 9.1, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N'}

cvssV4_0

{'score': 9.3, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N'}


Subscriptions

Cyrusimap Cyrus-sasl
cve-icon MITRE

Status: PUBLISHED

Assigner: VulnCheck

Published:

Updated: 2026-11-15T13:47:23.552Z

Reserved: 2026-11-15T13:41:10.001Z

Link: CVE-2026-129483

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-11-15T14:17:27.530

Modified: 2026-11-15T14:17:27.530

Link: CVE-2026-129483

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-11-15T16:15:15Z

Weaknesses