Vulnerability Description
There's a vulnerability in the libssh package where when a libssh consumer passes in an unexpectedly large input buffer to ssh_get_fingerprint_hash() function. In such cases the bin_to_base64() function can experience an integer overflow leading to a memory under allocation, when that happens it's possible that the program perform out of bounds write leading to a heap corruption. This issue affects only 32-bits builds of libssh.
CVSS Score
MEDIUM
Related Weaknesses (CWE)
References
- https://access.redhat.com/errata/RHSA-2026:18683
- https://access.redhat.com/security/cve/CVE-2025-4877
- https://bugzilla.redhat.com/show_bug.cgi?id=2376193
- https://git.libssh.org/projects/libssh.git/commit/?h=stable-0.11&id=6fd9cc8ce395
- https://www.libssh.org/security/advisories/CVE-2025-4877.txt
FAQ
What is CVE-2025-4877?
CVE-2025-4877 is a vulnerability with a CVSS score of 4.5 (MEDIUM). There's a vulnerability in the libssh package where when a libssh consumer passes in an unexpectedly large input buffer to ssh_get_fingerprint_hash() function. In such cases the bin_to_base64() functi...
How severe is CVE-2025-4877?
CVE-2025-4877 has been rated MEDIUM with a CVSS base score of 4.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2025-4877?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.