Out-of-bounds Read in Libssh
CVE-2026-59842
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.
Vulnerability class: Buffer Overflow
EPSS: 0.004 (34.0th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 3.7 (Low). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N.
Affected products
- Libssh
- Red Hat Enterprise Linux 10
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9
- Red Hat Hardened Images — versions 0.12.1-4.hum1
- Redhat Enterprise_linux — versions 10.0
- Redhat Hardened_images
Weakness classification (CWE)
References
- secalert@redhat.com (x_refsource_REDHAT, vdb-entry, Vendor Advisory)
- secalert@redhat.com (x_refsource_REDHAT, issue-tracking, Issue Tracking, Vendor Advisory)
- secalert@redhat.com (x_refsource_REDHAT, vendor-advisory, Vendor Advisory)
- secalert@redhat.com (x_refsource_REDHAT, vendor-advisory)
Frequently asked questions
- What is CVE-2026-59842?
- CVE-2026-59842 is a low-severity vulnerability in Libssh, classified under Out-of-bounds Read. CVSS score: 3.7/10. Published 2026-07-21.
- How severe is CVE-2026-59842?
- Low severity. CVSS v3 base score is 3.7 out of 10.