Paper/Archive/CVE-2026-2771

CVE-2026-2771

Mozilla Firefox — Undefined behavior in the DOM: Core & HTML component

Description · from the CVE record

Undefined behavior in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 148, Firefox ESR 115.33, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8.

Affected

ProductAffectedFixed inSource
Firefoxsee advisory115.33CNA
Thunderbirdsee advisory140.8CNA
Red Hat Enterprise Linux 10see advisory0:140.8.0-2.el10_1redhat-SADP
Red Hat Enterprise Linux 10see advisory0:140.8.0-2.el10_1redhat-SADP
Red Hat Enterprise Linux 10.0 Extended Update Supportsee advisory0:140.8.0-2.el10_0redhat-SADP
Red Hat Enterprise Linux 10.0 Extended Update Supportsee advisory0:140.8.0-2.el10_0redhat-SADP
Red Hat Enterprise Linux 7 Extended Lifecycle Supportsee advisory0:140.8.0-2.el7_9redhat-SADP
Red Hat Enterprise Linux 8see advisory0:140.8.0-2.el8_10redhat-SADP
Red Hat Enterprise Linux 8see advisory0:140.8.0-1.el8_10redhat-SADP
Red Hat Enterprise Linux 8.2 Advanced Update Supportsee advisory0:140.8.0-2.el8_2redhat-SADP
Red Hat Enterprise Linux 8.2 Advanced Update Supportsee advisory0:140.8.0-1.el8_2redhat-SADP
Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Supportsee advisory0:140.8.0-2.el8_4redhat-SADP

Scores by source

CISA ADP9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
redhat-SADP (CNA)7.5CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
CISA ADPSSVCExploitation: none · Automatable: yes · Technical impact: total

References

refbugzilla.mozilla.org/show_bug.cgi?id=2014593refmozilla.org/security/advisories/mfsa2026-13refmozilla.org/security/advisories/mfsa2026-14refmozilla.org/security/advisories/mfsa2026-15refmozilla.org/security/advisories/mfsa2026-16refmozilla.org/security/advisories/mfsa2026-17refaccess.redhat.com/security/cve/CVE-2026-2771refbugzilla.redhat.com/show_bug.cgi?id=2442288refsecurity.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-2771.jsonadvisoryaccess.redhat.com/errata/RHSA-2026:3984advisoryaccess.redhat.com/errata/RHSA-2026:3976advisoryaccess.redhat.com/errata/RHSA-2026:4260advisoryaccess.redhat.com/errata/RHSA-2026:3361advisoryaccess.redhat.com/errata/RHSA-2026:3517advisoryaccess.redhat.com/errata/RHSA-2026:3338advisoryaccess.redhat.com/errata/RHSA-2026:3515advisoryaccess.redhat.com/errata/RHSA-2026:3492advisoryaccess.redhat.com/errata/RHSA-2026:4432advisoryaccess.redhat.com/errata/RHSA-2026:3491advisoryaccess.redhat.com/errata/RHSA-2026:3980advisoryaccess.redhat.com/errata/RHSA-2026:3495advisoryaccess.redhat.com/errata/RHSA-2026:3979advisoryaccess.redhat.com/errata/RHSA-2026:3494advisoryaccess.redhat.com/errata/RHSA-2026:4022advisoryaccess.redhat.com/errata/RHSA-2026:3493advisoryaccess.redhat.com/errata/RHSA-2026:3983advisoryaccess.redhat.com/errata/RHSA-2026:4152advisoryaccess.redhat.com/errata/RHSA-2026:3978advisoryaccess.redhat.com/errata/RHSA-2026:3496advisoryaccess.redhat.com/errata/RHSA-2026:3981advisoryaccess.redhat.com/errata/RHSA-2026:3497advisoryaccess.redhat.com/errata/RHSA-2026:3982advisoryaccess.redhat.com/errata/RHSA-2026:3339advisoryaccess.redhat.com/errata/RHSA-2026:3516