Description
A flaw was found in libssh. During server-side GSSAPI key exchange, a client-supplied Curve25519 public key shorter than the expected length is copied without proper length validation, leading to an out-of-bounds heap read. This could allow a remote unauthenticated attacker to disclose small amounts of server memory.
Affected products
libssh: libssh; redhat: hardened images; redhat: enterprise linux; redhat: enterprise linux for els; redhat: enterprise linux for eus; redhat: enterprise linux for ibm z systems; redhat: enterprise linux for ibm z systems els; redhat: enterprise linux for ibm z systems eus; redhat: enterprise linux for power little endian; redhat: enterprise linux for power little endian els; redhat: enterprise linux for power little endian eus
References4
- access.redhat.com/errata/RHSA-2026:55855 Vendor Advisory
- access.redhat.com/security/cve/CVE-2026-59842 Vendor Advisory
- bugzilla.redhat.com/show_bug.cgi?id=2498168 Issue TrackingVendor Advisory
- access.redhat.com/errata/RHSA-2026:42922 Issue Tracking
Metrics
- CVSS 3.1
-
5.3
MEDIUM
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N - EPSS — exploit probability
- 0% percentile: 43 · as of 14 November 2026
- CWE
- CWE-125
Could this be exploited in your environment?
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