SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2025-5372

A flaw was found in libssh versions built with OpenSSL versions older than 3.0, specifically in the ssh_kdf() function responsible for key derivation.

HIGH 8.8EPSS 0.43%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.43%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

A flaw was found in libssh versions built with OpenSSL versions older than 3.0, specifically in the ssh_kdf() function responsible for key derivation. Due to inconsistent interpretation of return values where OpenSSL uses 0 to indicate failure and libssh uses 0 for success—the function may mistakenly return a success status even when key derivation fails. This results in uninitialized cryptographic key buffers being used in subsequent communication, potentially compromising SSH sessions' confidentiality, integrity, and availability.

CVSS 3.1
8.8 HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS
0.43% probability · 37th percentile
CISA KEV
Not listed
Weakness
CWE-682
Affected
libssh/libssh · redhat/openshift container platform · redhat/enterprise linux
Source
secalert@redhat.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.