SB20260428203 - Fedora 44 update for dovecot



SB20260428203 - Fedora 44 update for dovecot

Published: April 28, 2026

Security Bulletin ID SB20260428203
CSH Severity
Medium
Patch available
YES
Number of vulnerabilities 2
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 2 vulnerabilities.


1) Resource exhaustion (CVE-ID: CVE-2026-27858)

CWE-ID: CWE-400 - Resource exhaustion

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green


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

The vulnerability exists due to uncontrolled resource consumption in managesieve-login service when processing pre-authentication data. A remote attacker can send a specially crafted message before authentication to cause a denial of service.


2) Resource exhaustion (CVE-ID: CVE-2026-27857)

CWE-ID: CWE-400 - Resource exhaustion

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:L/E:U/U:Green


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

The vulnerability exists due to uncontrolled resource consumption in imap-login process when handling malformed NOOP commands. A remote user can send a specially crafted command with excessive parentheses to cause a denial of service.


Remediation

Install update from vendor's website.