CVE-2026-100772
published 2026-09-29CVE-2026-100772: 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…
PriorityP346high8.8CVSS 3.1
AVNACLPRNUIRSUCHIHAH
EPSS
0.31%
22.5th percentile
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
16 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| mozilla | firefox | < Firefox 157 | Firefox 157 |
| mozilla | firefox | — | — |
| mozilla | firefox | >= 140.0.0 < 140.17.0 | 140.17.0 |
| mozilla | firefox | >= 153.0 < 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 153.4 | Firefox ESR 153.4 |
| mozilla | thunderbird | < Thunderbird 157 | Thunderbird 157 |
| mozilla | thunderbird | < Thunderbird 153.4 | Thunderbird 153.4 |
| mozilla | thunderbird | < Thunderbird 140.17 | Thunderbird 140.17 |
| 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
nvdv3.18.8HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
vendor_redhat8.8HIGH
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VulDB
Mozilla Firefox up to 140.16/153.3/156 Core use after free (WID-SEC-2026-3654)
vuldb·2026-10-03·CVSS 8.8
CVE-2026-100772 [HIGH] Mozilla Firefox up to 140.16/153.3/156 Core use after free (WID-SEC-2026-3654)
A vulnerability was found in Mozilla Firefox up to 140.16/153.3/156 and classified as critical. This issue affects some unknown processing of the component Core. Such manipulation leads to use after free.
This vulnerability is listed as CVE-2026-100772. The attack may be performed from remote. There is no available exploit.
It is suggested to upgrade the affected component.
GHSA
Use-after-free in the DOM: Core & HTML component.
ghsa_unreviewed·2026-09-29
CVE-2026-100772 [HIGH] CWE-416 Use-after-free in the DOM: Core & HTML component.
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.
Red Hat
firefox: thunderbird: Use-after-free in the DOM: Core & HTML component
vendor_redhat·2026-09-29·CVSS 8.8
CVE-2026-100772 [HIGH] CWE-416 firefox: thunderbird: Use-after-free in the DOM: Core & HTML component
firefox: thunderbird: Use-after-free in the DOM: Core & HTML component
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.
A flaw was found in Firefox and Thunderbird. The Mozilla Foundation's Security Advisory describes the following issue:
Use-after-free in the DOM: Core & HTML component
Statement: Red Hat Product Security rates the severity of this flaw as determined by the Mozilla Foundation Security Advisory.
Mitigation: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or
Mozilla
Mozilla Foundation Security Advisory 2026-101: CVE-2026-100772
vendor_mozilla·CVSS 8.8
CVE-2026-100772 [HIGH] Mozilla Foundation Security Advisory 2026-101: CVE-2026-100772
Mozilla Foundation Security Advisory 2026-101
CVE: CVE-2026-100772
Product: Thunderbird
Impact: low
Fixed in: Thunderbird 157
Mozilla
Mozilla Foundation Security Advisory 2026-99: CVE-2026-100772
vendor_mozilla·CVSS 8.8
CVE-2026-100772 [HIGH] Mozilla Foundation Security Advisory 2026-99: CVE-2026-100772
Mozilla Foundation Security Advisory 2026-99
CVE: CVE-2026-100772
Product: Firefox ESR
Impact: moderate
Fixed in: Firefox ESR 140.17
Mozilla
Mozilla Foundation Security Advisory 2026-97: CVE-2026-100772
vendor_mozilla·CVSS 8.8
CVE-2026-100772 [HIGH] Mozilla Foundation Security Advisory 2026-97: CVE-2026-100772
Mozilla Foundation Security Advisory 2026-97
CVE: CVE-2026-100772
Product: Firefox
Impact: low
Fixed in: Firefox 157
Mozilla
Mozilla Foundation Security Advisory 2026-103: CVE-2026-100772
vendor_mozilla·CVSS 8.8
CVE-2026-100772 [HIGH] Mozilla Foundation Security Advisory 2026-103: CVE-2026-100772
Mozilla Foundation Security Advisory 2026-103
CVE: CVE-2026-100772
Product: Thunderbird
Impact: low
Fixed in: Thunderbird 153.4
Mozilla
Mozilla Foundation Security Advisory 2026-102: CVE-2026-100772
vendor_mozilla·CVSS 8.8
CVE-2026-100772 [HIGH] Mozilla Foundation Security Advisory 2026-102: CVE-2026-100772
Mozilla Foundation Security Advisory 2026-102
CVE: CVE-2026-100772
Product: Thunderbird
Impact: moderate
Fixed in: Thunderbird 140.17
Mozilla
Mozilla Foundation Security Advisory 2026-100: CVE-2026-100772
vendor_mozilla·CVSS 8.8
CVE-2026-100772 [HIGH] Mozilla Foundation Security Advisory 2026-100: CVE-2026-100772
Mozilla Foundation Security Advisory 2026-100
CVE: CVE-2026-100772
Product: Firefox ESR
Impact: low
Fixed in: Firefox ESR 153.4
No detection rules found.
No public exploits indexed.
https://bugzilla.mozilla.org/show_bug.cgi?id=2068340https://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