Home / mailings [SECURITY] [DSA 6283-1] firefox-esr security update
Posted on 20 May 2026
Debian Security Advisory- -------------------------------------------------------------------------
Debian Security Advisory DSA-6283-1 security@debian.org
https://www.debian.org/security/ Moritz Muehlenhoff
May 20, 2026 https://www.debian.org/security/faq
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Package : firefox-esr
CVE ID : CVE-2026-8388 CVE-2026-8391 CVE-2026-8401 CVE-2026-8946
CVE-2026-8947 CVE-2026-8950 CVE-2026-8953 CVE-2026-8954
CVE-2026-8955 CVE-2026-8956 CVE-2026-8957 CVE-2026-8958
CVE-2026-8961 CVE-2026-8962 CVE-2026-8968 CVE-2026-8970
CVE-2026-8974 CVE-2026-8975
Multiple security issues have been found in the Mozilla Firefox web
browser, which could potentially result in the execution of arbitrary
code, bypass of the same-origin policy, privilege escalation, information
disclosure, spoofing or sandbox escape.
For the oldstable distribution (bookworm), these problems have been fixed
in version 140.11.0esr-1~deb12u1.
For the stable distribution (trixie), these problems have been fixed in
version 140.11.0esr-1~deb13u1.
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/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/
Mailing list: debian-security-announce@lists.debian.org
