Mozilla security advisory (AV26-644)
Serial number: AV26-644 Date: June 30, 2026 On June 30, 2026, Mozilla published a security advisory to address a vulnerability in the following product: Firefox – versions prior to 152.04 Thunderbird – versions prior to 140.12.1 Thunderbird – versions prior to 152.01 The Cyber Centre encourages users and administrators to review the provided web links and apply the necessary updates. Mozilla Foundation Security Advisory 2026-62 Mozilla Security Advisories
CSIRTS triage
- What
- A vulnerability has been identified in Firefox and Thunderbird.
- Who is affected
- Users of affected versions of Firefox and Thunderbird.
- Urgency
- Remediation is necessary to ensure security, though specific details on exploitation are not provided.
- Action
- Update to the latest versions of Firefox and Thunderbird.
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Details
Original advisory: https://cyber.gc.ca/en/alerts-advisories/mozilla-security-advisory-av26-644
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