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CVE-2025-4877

Libssh: write beyond bounds in binary to base64 conversion functions

Published: Aug 20, 2025Updated: Jun 30, 2026 Sources: CVE List NVD BDUCWE-787

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.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:LAC:HPR:LUI:NS:UC:LI:LA:L
Exploitability
AV:LAttack Vector
Local
AC:HAttack Complexity
High
PR:LPrivileges Required
Low
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:LConfidentiality
Low
I:LIntegrity
Low
A:LAvailability
Low

Weaknesses

Affected Products

and 8 more affected products View all →

Exploitability

Official Patch Available

Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

2 techniques
Initial Access
Privilege Escalation
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References

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