Description
A flaw was found in libssh versions built with OpenSSL versions older than 3.0, specifically in the ssh_kdf() function responsible for key derivation. Due to inconsistent interpretation of return values where OpenSSL uses 0 to indicate failure and libssh uses 0 for success—the function may mistakenly return a success status even when key derivation fails. This results in uninitialized cryptographic key buffers being used in subsequent communication, potentially compromising SSH sessions' confidentiality, integrity, and availability.
Affected products
libssh: libssh; redhat: openshift container platform; redhat: enterprise linux
References7
- access.redhat.com/errata/RHSA-2025:21977
- access.redhat.com/errata/RHSA-2025:23024
- access.redhat.com/errata/RHSA-2026:20610
- access.redhat.com/errata/RHSA-2026:24349
- access.redhat.com/errata/RHSA-2026:25911
- access.redhat.com/security/cve/CVE-2025-5372 Third Party Advisory
- bugzilla.redhat.com/show_bug.cgi?id=2369388 Issue TrackingThird Party Advisory
Metrics
- CVSS 3.1
-
8.8
HIGH
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 1% percentile: 44 · as of 7 November 2026
- CWE
- CWE-682
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