CVE-2026-100770
published 2026-09-29CVE-2026-100770: Sandbox escape due to use-after-free in the DOM: Content Processes component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird…
PriorityP347critical9.6CVSS 3.1
AVNACLPRNUIRSCCHIHAH
EPSS
0.32%
23.3th percentile
Sandbox escape due to use-after-free in the DOM: Content Processes component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17, Thunderbird 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17.
Affected
18 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| mozilla | firefox | < Firefox 157 | Firefox 157 |
| mozilla | firefox | — | — |
| mozilla | firefox | >= 115.0 < 115.42.0 | 115.42.0 |
| mozilla | firefox | >= 140.0.0 < 140.17.0 | 140.17.0 |
| mozilla | firefox | >= 153.0.0 < 153.4.0 | 153.4.0 |
| mozilla | firefox | >= 154.0.0 < 157.0.0 | 157.0.0 |
| mozilla | firefox_esr | < Firefox ESR 140.17 | Firefox ESR 140.17 |
| mozilla | firefox_esr | < Firefox ESR 115.42 | Firefox ESR 115.42 |
| mozilla | firefox_esr | < Firefox ESR 153.4 | Firefox ESR 153.4 |
| mozilla | thunderbird | < Thunderbird 140.17 | Thunderbird 140.17 |
| mozilla | thunderbird | < Thunderbird 157 | Thunderbird 157 |
| mozilla | thunderbird | < Thunderbird 153.4 | Thunderbird 153.4 |
| mozilla | thunderbird | — | — |
| mozilla | thunderbird | >= 140.0 < 140.17.0 | 140.17.0 |
| mozilla | thunderbird | >= 153.0 < 153.4.0 | 153.4.0 |
| mozilla | thunderbird | >= 154.0 < 157.0 | 157.0 |
| rhel10 | firefox-flatpak | — | — |
| rhel10 | thunderbird-flatpak | — | — |
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: Sandbox escape due to use-after-free in the DOM: Content Processes component
vendor_redhat·2026-09-29·CVSS 9.6
CVE-2026-100770 [CRITICAL] CWE-825 firefox: Sandbox escape due to use-after-free in the DOM: Content Processes component
firefox: Sandbox escape due to use-after-free in the DOM: Content Processes component
Sandbox escape due to use-after-free in the DOM: Content Processes component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17, Thunderbird 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17.
A flaw was found in Firefox. The Mozilla Foundation's Security Advisory describes the following issue:
Sandbox escape due to use-after-free in the DOM: Content Processes component
Statement: Red Hat Product Security rates the severity of this flaw as determined by the Mozilla Foundation Security Advisory.
Package: firefox (Red Hat Enterprise Linux 10) - Affected
Package: rhel10/firefox-flatpak (Red Hat Enterprise Linux 10) - Affected
Package: rhel10/thunderbird-
Mozilla
Mozilla Foundation Security Advisory 2026-102: CVE-2026-100770
vendor_mozilla·CVSS 9.6
CVE-2026-100770 [CRITICAL] Mozilla Foundation Security Advisory 2026-102: CVE-2026-100770
Mozilla Foundation Security Advisory 2026-102
CVE: CVE-2026-100770
Product: Thunderbird
Impact: moderate
Fixed in: Thunderbird 140.17
Mozilla
Mozilla Foundation Security Advisory 2026-101: CVE-2026-100770
vendor_mozilla·CVSS 9.6
CVE-2026-100770 [CRITICAL] Mozilla Foundation Security Advisory 2026-101: CVE-2026-100770
Mozilla Foundation Security Advisory 2026-101
CVE: CVE-2026-100770
Product: Thunderbird
Impact: low
Fixed in: Thunderbird 157
Mozilla
Mozilla Foundation Security Advisory 2026-103: CVE-2026-100770
vendor_mozilla·CVSS 9.6
CVE-2026-100770 [CRITICAL] Mozilla Foundation Security Advisory 2026-103: CVE-2026-100770
Mozilla Foundation Security Advisory 2026-103
CVE: CVE-2026-100770
Product: Thunderbird
Impact: low
Fixed in: Thunderbird 153.4
Mozilla
Mozilla Foundation Security Advisory 2026-99: CVE-2026-100770
vendor_mozilla·CVSS 9.6
CVE-2026-100770 [CRITICAL] Mozilla Foundation Security Advisory 2026-99: CVE-2026-100770
Mozilla Foundation Security Advisory 2026-99
CVE: CVE-2026-100770
Product: Firefox ESR
Impact: moderate
Fixed in: Firefox ESR 140.17
Mozilla
Mozilla Foundation Security Advisory 2026-98: CVE-2026-100770
vendor_mozilla·CVSS 9.6
CVE-2026-100770 [CRITICAL] Mozilla Foundation Security Advisory 2026-98: CVE-2026-100770
Mozilla Foundation Security Advisory 2026-98
CVE: CVE-2026-100770
Product: Firefox ESR
Impact: moderate
Fixed in: Firefox ESR 115.42
Mozilla
Mozilla Foundation Security Advisory 2026-97: CVE-2026-100770
vendor_mozilla·CVSS 9.6
CVE-2026-100770 [CRITICAL] Mozilla Foundation Security Advisory 2026-97: CVE-2026-100770
Mozilla Foundation Security Advisory 2026-97
CVE: CVE-2026-100770
Product: Firefox
Impact: low
Fixed in: Firefox 157
Mozilla
Mozilla Foundation Security Advisory 2026-100: CVE-2026-100770
vendor_mozilla·CVSS 9.6
CVE-2026-100770 [CRITICAL] Mozilla Foundation Security Advisory 2026-100: CVE-2026-100770
Mozilla Foundation Security Advisory 2026-100
CVE: CVE-2026-100770
Product: Firefox ESR
Impact: low
Fixed in: Firefox ESR 153.4
VulDB
Mozilla Firefox up to 115.41/140.16/153.3/156 DOM Content Processes use after free (WID-SEC-2026-3654)
vuldb·2026-10-03·CVSS 9.6
CVE-2026-100770 [CRITICAL] Mozilla Firefox up to 115.41/140.16/153.3/156 DOM Content Processes use after free (WID-SEC-2026-3654)
A vulnerability has been found in Mozilla Firefox up to 115.41/140.16/153.3/156 and classified as critical. Affected by this vulnerability is an unknown functionality of the component DOM Content Processes. The manipulation leads to use after free.
This vulnerability is listed as CVE-2026-100770. The attack may be initiated remotely. There is no available exploit.
The affected component should be upgraded.
GHSA
Sandbox escape due to use-after-free in the DOM: Content Processes component.
ghsa_unreviewed·2026-09-29
CVE-2026-100770 [CRITICAL] CWE-416 Sandbox escape due to use-after-free in the DOM: Content Processes component.
Sandbox escape due to use-after-free in the DOM: Content Processes component. This vulnerability was fixed in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17.
No detection rules found.
No public exploits indexed.
https://bugzilla.mozilla.org/show_bug.cgi?id=2068322https://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/mfsa2026-98/https://www.mozilla.org/security/advisories/mfsa2026-99/
2026-09-29
Published