4.5Medium
CVE-2025-4877
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.
What this means for your business
- An attacker can use it only with access to the machine itself, with an ordinary user login, and without anyone at your company clicking anything.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
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Scoring
- CVSS
- 4.5 (v3.1)
- Vector
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L- Weakness
- CWE-787
- Assigned by
- secalert@redhat.com
Dates
- Published
- 2025-08-20
- Last modified
- 2026-08-31
- Sources
- NVD
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=6fd9cc8ce3958092a1aae11f1f2e911b2747732d
- https://www.libssh.org/security/advisories/CVE-2025-4877.txt