Advisory Published

MFSA2021-40: Security Vulnerabilities fixed in Firefox ESR 91.1

First published: Tue Sep 07 2021(Updated: )

Security Vulnerabilities fixed in Firefox ESR 91.1

Affected SoftwareAffected VersionHow to fix
<91.1
91.1

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Child vulnerabilities

(Contains the following vulnerabilities)

Frequently Asked Questions

  • What is the severity of MFSA2021-40?

    The severity of MFSA2021-40 includes several security vulnerabilities that could potentially lead to data leaks or crashes.

  • How do I fix MFSA2021-40?

    To fix MFSA2021-40, update to Firefox ESR version 91.1 or higher.

  • What types of vulnerabilities are addressed in MFSA2021-40?

    MFSA2021-40 addresses vulnerabilities related to memory safety, security flaws, and potential crashes.

  • Which versions of Firefox ESR are affected by MFSA2021-40?

    MFSA2021-40 affects all versions of Firefox ESR prior to 91.1.

  • Is there a workaround for the vulnerabilities in MFSA2021-40?

    There are no reported workarounds for the vulnerabilities in MFSA2021-40; upgrading is necessary to mitigate risks.

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