CVE-2025-4877
CVSS 4.5 MediumEPSS 0.0%
- CVSS Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L
- Published: 2025-08-20T13:15:28.890
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.
Related CVE by CWE
No related CWE found.
Top CVE for Vendor
No vendor taxonomy on this entry.
Recently Exploited Similar Vulnerabilities
No recent KEV-listed items for this vendor/product.
How to fix CVE-2025-4877
CVE-2025-4877 is a medium severity vulnerability affecting the affected product.
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 […]
Exploit Difficulty: VERY HARD
⏱️ Time to exploit: Days or weeks
🛠️ Required skills: Expert-level security skills
💰 Public exploits: Not publicly available
How to Fix:
- Check if you're running the affected product
- Update to the latest patched version
- If patching is not immediately possible: restrict network exposure, apply least-privilege access
- Test the fix in a staging environment first
- Review logs for signs of exploitation
- Monitor for IOCs (Indicators of Compromise)
- Enable automatic security updates
- Set up vulnerability monitoring
- Review and harden security configurations
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 […]
Exploit Difficulty: VERY HARD
⏱️ Time to exploit: Days or weeks
🛠️ Required skills: Expert-level security skills
💰 Public exploits: Not publicly available
How to Fix:
1 Identify affected systems
- Check if you're running the affected product
2 Immediate actions
- Update to the latest patched version
- If patching is not immediately possible: restrict network exposure, apply least-privilege access
3 Verification
- Test the fix in a staging environment first
- Review logs for signs of exploitation
- Monitor for IOCs (Indicators of Compromise)
4 Long-term prevention
- Enable automatic security updates
- Set up vulnerability monitoring
- Review and harden security configurations
Exploit Difficulty Assessment
VERY HARD
Time to Exploit: Days or weeks
Skills Required: Expert-level security skills
Public Exploits: Not publicly available
Vulnerability Timeline
Aug 20, 2025
Vulnerability Published
CVE details first published to NVD database
Nov 12, 2025
Imported to Database
Added to this CVE tracking system
Detection Rules & IOCs
No specific detection rules generated for this vulnerability type.
No vendor/product data available.