Description
A flaw was found in libssh. The API function `ssh_get_hexa()` is vulnerable to a denial of service when processing zero-length input. This can be exploited remotely by an attacker during GSSAPI (Generic Security Service Application Program Interface) authentication if the server's logging verbosity is set to `SSH_LOG_PACKET (3)` or higher. Successful exploitation could lead to a self-Denial of Service of the per-connection daemon process.
Affected products
libssh: libssh; redhat: hardened images; redhat: openshift container platform; redhat: enterprise linux
References6
- access.redhat.com/errata/RHSA-2026:7067 Vendor Advisory
- access.redhat.com/security/cve/CVE-2026-0966 MitigationVendor Advisory
- bugzilla.redhat.com/show_bug.cgi?id=2433121 Issue TrackingVendor Advisory
- access.redhat.com/errata/RHSA-2026:18160
- access.redhat.com/errata/RHSA-2026:18683
- www.libssh.org/2026/02/10/libssh-0-12-0-and-0-11-4-security-rel… Release Notes
Metrics
- CVSS 3.1
-
8.2
HIGH
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H - EPSS — exploit probability
- 1% percentile: 50 · as of 12 November 2026
- CWE
- CWE-124
Could this be exploited in your environment?
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