CVE-2026-59849

Publication date 21 July 2026

Last updated 31 August 2026

Ubuntu priority

Medium

Why this priority?

Cvss 3 Severity Score

3.1 · Low

Score breakdown

Description

A flaw was found in libssh. Logic errors in automatic certificate-based public key authentication can cause libssh clients to loop indefinitely when configured certificates are missing or repeatedly rejected by a server, leading to denial of service.

Read the notes from the security team

Status

Package Ubuntu Release Status
libssh 26.04 LTS resolute
Fixed 0.11.3-1ubuntu2.1
24.04 LTS noble
Not affected
22.04 LTS jammy
Not affected
20.04 LTS focal
Not affected
18.04 LTS bionic
Not affected
16.04 LTS xenial
Not affected

Notes

mdeslaur

introduced in 0.11.0 by: https://github.com/libssh/libssh-mirror/commit/aae1bc10588787e1fe15c84b9f8f76176ac8e603

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

CVSS version: CVSS v3.0

Base score 3.1 · Low

Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L

References

Related Ubuntu Security Notices (USN)

    • USN-8699-1
    • libssh vulnerabilities
    • 31 August 2026

Other references

Access our resources on patching vulnerabilities