CVE-2025-5987

Publication date 25 June 2025

Last updated 10 July 2025

Ubuntu priority

Medium

Why this priority?

Cvss 3 Severity Score

5.0 · Medium

Score breakdown

A flaw was found in libssh when using the ChaCha20 cipher with the OpenSSL library. If an attacker manages to exhaust the heap space, this error is not detected and may lead to libssh using a partially initialized cipher context. This occurs because the OpenSSL error code returned aliases with the SSH_OK code, resulting in libssh not properly detecting the error returned by the OpenSSL library. This issue can lead to undefined behavior, including compromised data confidentiality and integrity or crashes.

Status

Package Ubuntu Release Status
libssh 25.04 plucky
Fixed 0.11.1-1ubuntu0.1
24.10 oracular
Fixed 0.10.6-3ubuntu1.1
24.04 LTS noble
Fixed 0.10.6-2ubuntu0.1
22.04 LTS jammy
Not affected
20.04 LTS focal
Not affected
18.04 LTS bionic
Not affected
16.04 LTS xenial
Not affected

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package Patch details
libssh

Severity score breakdown

Parameter Value
Base score 5.0 · Medium
Attack vector Network
Attack complexity High
Privileges required Low
User interaction None
Scope Unchanged
Confidentiality Low
Integrity impact Low
Availability impact Low
Vector CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L

References

Related Ubuntu Security Notices (USN)

Other references