Ref# ADV2025_418 | Date: Dec 10th 2025

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Mozilla published a security advisory highlighting vulnerabilities in the following product on December 9th, 2025. It is recommended that you take the necessary precautions by ensuring your products are always updated. 

• Firefox – versions prior to 146 

• Firefox ESR – versions prior to 115.31 

• Firefox ESR – versions prior to 140.6 

For more information on these updates, you can follow these URLs: 

• Mozilla Foundation Security Advisory 2025-92 

• Mozilla Foundation Security Advisory 2025-93 

• Mozilla Foundation Security Advisory 2025-94 

• Mozilla Security Advisories 

The Guyana National CIRT recommends that users and administrators review these updates and apply them where necessary. 

References 

• Mozilla Security Advisory (December 9th, 2025). Retrieved from Mozilla. https://www.mozilla.org/en-US/security/advisories/mfsa2025-92/ 

  

• Mozilla Security Advisory. (December 9th, 2025). Retrieved from Canadian Centre for Cyber Security. https://www.cyber.gc.ca/en/alerts-advisories/mozilla-security-advisory-av25-819