Number: AV21-089
Date: 23 February 2021
On 23 February 2021 Mozilla published Security Advisories to address vulnerabilities in the following products:
- Firefox – versions prior to 86
- Firefox ESR – versions prior to 78.8
- Thunderbird – versions prior to 78.8
The Cyber Centre encourages users and administrators to review the provided web links and apply the necessary updates.
Firefox (MFSA 2021-07)
https://www.mozilla.org/en-US/security/advisories/mfsa2021-07/
Firefox ESR (MFSA 2021-08)
https://www.mozilla.org/en-US/security/advisories/mfsa2021-08/
Thunderbird (MFSA 2021-09)
https://www.mozilla.org/en-US/security/advisories/mfsa2021-09/
Note to Readers
The Canadian Centre for Cyber Security (Cyber Centre) operates as part of the Communications Security Establishment. We are Canada’s national authority on cyber security and we lead the government’s response to cyber security events. As Canada's national computer security incident response team, the Cyber Centre works in close collaboration with government departments, critical infrastructure, Canadian businesses and international partners to prepare for, respond to, mitigate, and recover from cyber events. We do this by providing authoritative advice and support, and coordinating information sharing and incident response. The Cyber Centre is outward-facing, welcoming partnerships that help build a stronger, more resilient cyber space in Canada.