SB2026040127 - Remote denial of service in Dovecot SASL implementation



SB2026040127 - Remote denial of service in Dovecot SASL implementation

Published: April 1, 2026

Security Bulletin ID SB2026040127
Severity
Medium
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Remote access
Highest impact Denial of service

Breakdown by Severity

Medium 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 security vulnerability.


1) Improper input validation (CVE-ID: CVE-2025-59028)

The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to improper input validation in SASL authentication handling when processing user-supplied data. A remote attacker can send a specially crafted request containing invalid base64 data to cause a denial of service.

The denial of service affects concurrent authentication sessions.


Remediation

Install update from vendor's website.