CVE-2025-8114
libssh: NULL Pointer Dereference in libssh KEX Session ID Calculation
Severity
ModerateRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · July 24, 2025
Updated · September 1, 2026
Description
A flaw was found in libssh, a library that implements the SSH protocol. When calculating the session ID during the key exchange (KEX) process, an allocation failure in cryptographic functions may lead to a NULL pointer dereference. This issue can cause the client or server to crash.
Statement
The Red Hat Product Security team has assessed the severity of this vulnerability as Moderate, due to its local attack vector and high complexity of exploitation. Although it requires specific allocation failure scenarios, successful exploitation can result in a crash of SSH clients or servers using libssh. This is caused by a NULL pointer dereference during the calculation of the KEX session ID.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
CVSS / CWE
CVSS 3.1 · 4.7CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
CWE-476 · NULL Pointer Dereference