firefox: Sandbox escape due to use-after-free in the DOM: Security component

cve CVE-2026-84121 1 source, 1 claim · Watch

Red Hat writes:
firefox: Sandbox escape due to use-after-free in the DOM: Security component the claim

What each source says

PropertySourceSaidMeans here
Cvss
cvss
Red Hat7.5
receipt
Source
Red Hat
Its words
7.5
Read by
field:cvss3_score
Said since
2026-09-29 09:44 UTC
Last answered
2026-10-02 18:04 UTC
Original
open at the source
What the source handed over
{
  "CVE": "CVE-2026-84121",
  "CWE": "CWE-825",
  "advisories": [
    "RHSA-2026:67129",
    "RHSA-2026:67133",
    "RHSA-2026:70642",
    "RHSA-2026:68549"
  ],
  "affected_packages": [
    "thunderbird-0:140.16.0-1.el9_8",
    "firefox-0:140.15.0-1.el8_10",
    "firefox-0:140.15.0-1.el9_8",
    "firefox-0:140.15.0-1.el10_2"
  ],
  "bugzilla": "2526753",
  "bugzilla_description": "firefox: Sandbox escape due to use-after-free in the DOM: Security component",
  "cvss3_score": "7.5",
  "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H",
  "cvss_score": null,
  "cvss_scoring_vector": null,
  "package_state": null,
  "public_date": "2026-09-01T12:18:41Z",
  "resource_url": "https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2026-84121.json",
  "severity": "important"
}
—
Cwe
cwe
Red HatCWE-825
receipt
Source
Red Hat
Its words
CWE-825
Read by
field:CWE
Said since
2026-09-29 09:44 UTC
Last answered
2026-10-02 18:04 UTC
Original
open at the source
What the source handed over
{
  "CVE": "CVE-2026-84121",
  "CWE": "CWE-825",
  "advisories": [
    "RHSA-2026:67129",
    "RHSA-2026:67133",
    "RHSA-2026:70642",
    "RHSA-2026:68549"
  ],
  "affected_packages": [
    "thunderbird-0:140.16.0-1.el9_8",
    "firefox-0:140.15.0-1.el8_10",
    "firefox-0:140.15.0-1.el9_8",
    "firefox-0:140.15.0-1.el10_2"
  ],
  "bugzilla": "2526753",
  "bugzilla_description": "firefox: Sandbox escape due to use-after-free in the DOM: Security component",
  "cvss3_score": "7.5",
  "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H",
  "cvss_score": null,
  "cvss_scoring_vector": null,
  "package_state": null,
  "public_date": "2026-09-01T12:18:41Z",
  "resource_url": "https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2026-84121.json",
  "severity": "important"
}
—
Packages
packages
Red Hatthunderbird-0:140.16.0-1.el9_8, firefox-0:140.15.0-1.el8_10, firefox-0:140.15.0-1.el9_8, firefox-0:140.15.0-1.el10_2
receipt
Source
Red Hat
Its words
thunderbird-0:140.16.0-1.el9_8, firefox-0:140.15.0-1.el8_10, firefox-0:140.15.0-1.el9_8, firefox-0:140.15.0-1.el10_2
Read by
field:affected_packages[]
Said since
2026-09-29 09:44 UTC
Last answered
2026-10-02 18:04 UTC
Original
open at the source
What the source handed over
{
  "CVE": "CVE-2026-84121",
  "CWE": "CWE-825",
  "advisories": [
    "RHSA-2026:67129",
    "RHSA-2026:67133",
    "RHSA-2026:70642",
    "RHSA-2026:68549"
  ],
  "affected_packages": [
    "thunderbird-0:140.16.0-1.el9_8",
    "firefox-0:140.15.0-1.el8_10",
    "firefox-0:140.15.0-1.el9_8",
    "firefox-0:140.15.0-1.el10_2"
  ],
  "bugzilla": "2526753",
  "bugzilla_description": "firefox: Sandbox escape due to use-after-free in the DOM: Security component",
  "cvss3_score": "7.5",
  "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H",
  "cvss_score": null,
  "cvss_scoring_vector": null,
  "package_state": null,
  "public_date": "2026-09-01T12:18:41Z",
  "resource_url": "https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2026-84121.json",
  "severity": "important"
}
—
Severity
severity
Red Hatimportant
A flaw that can easily compromise confidentiality, integrity or availability.
receipt
Source
Red Hat
Its words
important
Read by
field:severity
Said since
2026-09-29 09:44 UTC
Last answered
2026-10-02 18:04 UTC
Original
open at the source
What the source handed over
{
  "CVE": "CVE-2026-84121",
  "CWE": "CWE-825",
  "advisories": [
    "RHSA-2026:67129",
    "RHSA-2026:67133",
    "RHSA-2026:70642",
    "RHSA-2026:68549"
  ],
  "affected_packages": [
    "thunderbird-0:140.16.0-1.el9_8",
    "firefox-0:140.15.0-1.el8_10",
    "firefox-0:140.15.0-1.el9_8",
    "firefox-0:140.15.0-1.el10_2"
  ],
  "bugzilla": "2526753",
  "bugzilla_description": "firefox: Sandbox escape due to use-after-free in the DOM: Security component",
  "cvss3_score": "7.5",
  "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H",
  "cvss_score": null,
  "cvss_scoring_vector": null,
  "package_state": null,
  "public_date": "2026-09-01T12:18:41Z",
  "resource_url": "https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2026-84121.json",
  "severity": "important"
}
high

vulnerability

firefox: Sandbox escape due to use-after-free in the DOM: Security component
zetlyn/cve-redhat · 2026-09-01
cvss 7.5 cwe CWE-825 packages thunderbird-0:140.16.0-1.el9_8, firefox-0:140.15.0-1.el8_10, firefox-0:140.15.0-1.el9_8, firefox-0:140.15.0-1.el10_2 severity important source