CVE-2025-5987
HIGHDescription
A flaw was found in libssh when using the ChaCha20 cipher with the OpenSSL library. If an attacker manages to exhaust the heap space, this error is not detected and may lead to libssh using a partially initialized cipher context. This occurs because the OpenSSL error code returned aliases with the SSH_OK code, resulting in libssh not properly detecting the error returned by the OpenSSL library. This issue can lead to undefined behavior, including compromised data confidentiality and integrity or crashes.
CVSS v3 Vector
Exploitability
Impact
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Exploit Intelligence
Moderate risk: more likely to be exploited than 70% of all known CVEs.
References
- https://access.redhat.com/errata/RHSA-2025:23483
- https://access.redhat.com/errata/RHSA-2025:23484
- https://access.redhat.com/errata/RHSA-2026:0427
- https://access.redhat.com/errata/RHSA-2026:0428
- https://access.redhat.com/errata/RHSA-2026:0430
- https://access.redhat.com/errata/RHSA-2026:0431
- https://access.redhat.com/errata/RHSA-2026:0702
- https://access.redhat.com/errata/RHSA-2026:0978
- https://access.redhat.com/errata/RHSA-2026:0980
- https://access.redhat.com/errata/RHSA-2026:0985
- https://access.redhat.com/errata/RHSA-2026:0996
- https://access.redhat.com/errata/RHSA-2026:1539
- https://access.redhat.com/errata/RHSA-2026:1541
- https://access.redhat.com/errata/RHSA-2026:3415
- https://access.redhat.com/security/cve/CVE-2025-5987
- https://bugzilla.redhat.com/show_bug.cgi?id=2376219
- https://www.libssh.org/security/advisories/CVE-2025-5987.txt
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Start freeThis product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-03-20.