CVE-2025-61962

Publication date 4 October 2025

Last updated 11 November 2026

Ubuntu priority

Cvss 3 Severity Score

Description

In fetchmail before 6.5.6, the SMTP client can crash when authenticating upon receiving a 334 status code in a malformed context.

Status

Show unmaintained releases

Package	Ubuntu Release	Status
fetchmail	26.10 stonking	Fixed in 6.5.4-0ubuntu2
	26.04 LTS resolute	Fixed in 6.5.4-0ubuntu2
	25.10 questing	Fixed in 6.5.4-0ubuntu2
	25.04 plucky	Fixed in 6.4.39-1ubuntu0.1
	24.04 LTS noble	Fixed in 6.4.38-1ubuntu4.1
	22.04 LTS jammy	Fixed in 6.4.27-1ubuntu0.1
	20.04 LTS focal	Fixed in 6.4.2-2ubuntu0.1~esm1
	18.04 LTS bionic	Fixed in 6.3.26-3ubuntu0.1~18.04.1+esm1
	16.04 LTS xenial	Fixed in 6.3.26-2ubuntu0.1~esm1

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Patch details

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

Package	Patch details
fetchmail	Upstream: 4c3cebf

Severity score breakdown

CVSS version: CVSS v3.0

Base score 5.9 · Medium

Base metrics

Parameter	Value
Attack vector	Network
Attack complexity	High
Privileges required	None
User interaction	None
Scope	Unchanged
Confidentiality impact	None
Integrity impact	None
Availability impact	High

Scores

Parameter	Value
Base score	5.9 · Medium
Exploitability score	-
Impact score	-

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

References

Related Ubuntu Security Notices (USN)

USN-7838-1
fetchmail vulnerability
23 October 2025

USN-9013-1
Fetchmail vulnerabilities
9 November 2026