CVE-2026-100811
published 2026-09-29CVE-2026-100811: Sandbox escape due to use-after-free in the DOM: Core & HTML component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17…
PriorityP346critical9.6CVSS 3.1
AVNACLPRNUIRSCCHIHAH
EPSS
0.26%
16.5th percentile
Sandbox escape due to use-after-free in the DOM: Core & HTML component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17, Thunderbird 153.4, Firefox 157, and Firefox ESR 140.17.
Affected
13 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| mozilla | firefox | < Firefox 157 | Firefox 157 |
| mozilla | firefox | < 140.17.0 | 140.17.0 |
| mozilla | firefox | — | — |
| mozilla | firefox | >= 141.0 < 153.4.0 | 153.4.0 |
| mozilla | firefox | >= 154.0.0 < 157.0.0 | 157.0.0 |
| mozilla | firefox_esr | < Firefox ESR 153.4 | Firefox ESR 153.4 |
| mozilla | firefox_esr | < Firefox ESR 140.17 | Firefox ESR 140.17 |
| mozilla | thunderbird | < Thunderbird 157 | Thunderbird 157 |
| mozilla | thunderbird | < Thunderbird 153.4 | Thunderbird 153.4 |
| mozilla | thunderbird | < Thunderbird 140.17 | Thunderbird 140.17 |
| mozilla | thunderbird | < 140.17.0 | 140.17.0 |
| mozilla | thunderbird | >= 141.0 < 153.4.0 | 153.4.0 |
| mozilla | thunderbird | >= 154.0 < 157.0 | 157.0 |
CVSS provenance
nvdv3.19.6CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
vendor_redhat9.6CRITICAL
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Red Hat
firefox: firefox: Sandbox escape via use-after-free in DOM component
vendor_redhat·2026-09-29·CVSS 9.6
CVE-2026-100811 [CRITICAL] CWE-825 firefox: firefox: Sandbox escape via use-after-free in DOM component
firefox: firefox: Sandbox escape via use-after-free in DOM component
Sandbox escape due to use-after-free in the DOM: Core & HTML component. This vulnerability was fixed in Firefox ESR 153.4, Firefox 157, and Firefox ESR 140.17.
A flaw was found in Firefox. A use-after-free memory flaw in the Document Object Model (DOM) Core and HTML component allows a remote attacker to perform a sandbox escape. By enticing a user to visit a specially crafted web page, an attacker can leverage this vulnerability to execute arbitrary code outside the browser's restricted sandbox environment.
Package: firefox (Red Hat Enterprise Linux 10) - Affected
Package: firefox (Red Hat Enterprise Linux 7) - Affected
Package: firefox (Red Hat Enterprise Linux 8) - Affected
Package: firefox (Red Hat Enterprise Lin
Mozilla
Mozilla Foundation Security Advisory 2026-97: CVE-2026-100811
vendor_mozilla·CVSS 9.6
CVE-2026-100811 [CRITICAL] Mozilla Foundation Security Advisory 2026-97: CVE-2026-100811
Mozilla Foundation Security Advisory 2026-97
CVE: CVE-2026-100811
Product: Firefox
Impact: low
Fixed in: Firefox 157
Mozilla
Mozilla Foundation Security Advisory 2026-101: CVE-2026-100811
vendor_mozilla·CVSS 9.6
CVE-2026-100811 [CRITICAL] Mozilla Foundation Security Advisory 2026-101: CVE-2026-100811
Mozilla Foundation Security Advisory 2026-101
CVE: CVE-2026-100811
Product: Thunderbird
Impact: low
Fixed in: Thunderbird 157
Mozilla
Mozilla Foundation Security Advisory 2026-103: CVE-2026-100811
vendor_mozilla·CVSS 9.6
CVE-2026-100811 [CRITICAL] Mozilla Foundation Security Advisory 2026-103: CVE-2026-100811
Mozilla Foundation Security Advisory 2026-103
CVE: CVE-2026-100811
Product: Thunderbird
Impact: low
Fixed in: Thunderbird 153.4
Mozilla
Mozilla Foundation Security Advisory 2026-100: CVE-2026-100811
vendor_mozilla·CVSS 9.6
CVE-2026-100811 [CRITICAL] Mozilla Foundation Security Advisory 2026-100: CVE-2026-100811
Mozilla Foundation Security Advisory 2026-100
CVE: CVE-2026-100811
Product: Firefox ESR
Impact: low
Fixed in: Firefox ESR 153.4
Mozilla
Mozilla Foundation Security Advisory 2026-99: CVE-2026-100811
vendor_mozilla·CVSS 9.6
CVE-2026-100811 [CRITICAL] Mozilla Foundation Security Advisory 2026-99: CVE-2026-100811
Mozilla Foundation Security Advisory 2026-99
CVE: CVE-2026-100811
Product: Firefox ESR
Impact: moderate
Fixed in: Firefox ESR 140.17
Mozilla
Mozilla Foundation Security Advisory 2026-102: CVE-2026-100811
vendor_mozilla·CVSS 9.6
CVE-2026-100811 [CRITICAL] Mozilla Foundation Security Advisory 2026-102: CVE-2026-100811
Mozilla Foundation Security Advisory 2026-102
CVE: CVE-2026-100811
Product: Thunderbird
Impact: moderate
Fixed in: Thunderbird 140.17
GHSA
Sandbox escape due to use-after-free in the DOM: Core & HTML component.
ghsa_unreviewed·2026-09-29
CVE-2026-100811 [CRITICAL] CWE-416 Sandbox escape due to use-after-free in the DOM: Core & HTML component.
Sandbox escape due to use-after-free in the DOM: Core & HTML component. This vulnerability was fixed in Firefox ESR 153.4, Firefox 157, and Firefox ESR 140.17.
No detection rules found.
No public exploits indexed.
https://bugzilla.mozilla.org/show_bug.cgi?id=2067973https://www.mozilla.org/security/advisories/mfsa2026-100/https://www.mozilla.org/security/advisories/mfsa2026-101/https://www.mozilla.org/security/advisories/mfsa2026-102/https://www.mozilla.org/security/advisories/mfsa2026-103/https://www.mozilla.org/security/advisories/mfsa2026-97/https://www.mozilla.org/security/advisories/mfsa2026-99/
2026-09-29
Published