8.8

CVE-2025-5372: libssh Incorrect Calculation

CVSS: 8.8v3.1HighModified
AliasesRHSA-2025:21977RHSA-2025:23024RHSA-2026:20610
Published 04-07-2025Last modified 01-09-2026
Open JSON

Vulnerability summary

CVE-2025-5372 is a high (CVSS 8.8) Incorrect Calculation vulnerability in libssh. EPSS estimates a 0.50% chance of exploitation in the next 30 days, higher than 41.5% of scored vulnerabilities.

Overall risk
35/100
0100
Medium · default modelHow is this calculated?
CVSS score
8.8/10
010
High · v3.1 (NVD)
EPSS score
0.50%
0%100%
Low · +0.07 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 10 · Related 8
DLA-4385-1MGASA-2026-0189OPENSUSE-SU-2025:15243-1SUSE-SU-2025:02229-1SUSE-SU-2025:02278-1SUSE-SU-2025:02279-1

Timeline

  1. 04-07-2025
    PublishedVulnerability first disclosed.
  2. 01-09-2026
    Last modifiedVulnerability information updated.

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 metrics

5 scores · 5 sources · 1 version

EPSS trend

Probability

0.50%

Chance of exploitation in the next 30 days

Percentile

42%

Versus all other CVEs

30-day change

+0.07 pp

From 0.43% on 18-09-2026

18-09-202618-10-2026
EPSS score
0.50%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Redhat7 products
  • enterprise_linuxEOL6.0 | 7.0 | 8.0 | 9.0 | 10.0
  • openshift_container_platform4.0
  • libssh< 0:0.9.6-13.el8_8.2 | < 0:0.9.4-2.el8_4.2 | < 0:0.9.6-16.el8_10 | < 0:0.9.6-3.el9_0.2 | < 0:0.9.6-4.el8_6.2
  • libssh-config< 0:0.9.6-13.el8_8.2 | < 0:0.9.4-2.el8_4.2 | < 0:0.9.6-16.el8_10 | < 0:0.9.6-3.el9_0.2 | < 0:0.9.6-4.el8_6.2
  • libssh-debuginfo< 0:0.9.6-13.el8_8.2 | < 0:0.9.4-2.el8_4.2 | < 0:0.9.6-16.el8_10 | < 0:0.9.6-3.el9_0.2 | < 0:0.9.6-4.el8_6.2
Debian1 product
  • libssh< 0.10.6-0+deb12u2 | < 0.11.2-1
Libssh1 product
Ubuntu1 product
  • libsshAll versions (No fix recorded) | < 0.9.6-2ubuntu0.22.04.4 | < 0.10.6-2ubuntu0.1

4 vendors · 10 products

References

19 links
Show all 19 references