SB2026012911 - Information disclosure in Mozilla Thunderbird



SB2026012911 - Information disclosure in Mozilla Thunderbird

Published: January 29, 2026

Security Bulletin ID SB2026012911
Severity
Medium
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Remote access
Highest impact Information disclosure

Breakdown by Severity

Medium 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 security vulnerability.


1) Information disclosure (CVE-ID: CVE-2026-0818)

The vulnerability allows a remote attacker to gain access to potentially sensitive information.

The vulnerability exists due to the way CSS is handled within the application. A remote attacker can exfiltrate content from partially encrypted emails when allowing remote content. 


Remediation

Install update from vendor's website.