Debian: DSA-5156-1 Critical: Firefox-ESR Code Execution and Spoofing

Multiple security issues have been found in the Mozilla Firefox web
browser, which could potentially result in the execution of arbitrary
code, information disclosure or spoofing.

For the oldstable distribution (buster), these problems have been fixed
in version 91.10.0esr-1~deb10u1.

For the stable distribution (bullseye), these problems have been fixed in
version 91.10.0esr-1~deb11u1.

We recommend that you upgrade your firefox-esr packages.

For the detailed security status of firefox-esr please refer to
its security tracker page at:
https://security-tracker.debian.org/tracker/source-package/firefox-esr

Further information about Debian Security Advisories, how to apply
these updates to your system and frequently asked questions can be
found at: https://www.debian.org/security/