CVE-2026-100781
published 2026-09-29CVE-2026-100781: Sandbox escape due to incorrect boundary conditions in the Graphics: WebRender component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157…
PriorityP347critical9.6CVSS 3.1
AVNACLPRNUIRSCCHIHAH
EPSS
0.33%
24.0th percentile
Sandbox escape due to incorrect boundary conditions in the Graphics: WebRender 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
14 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| mozilla | firefox | < Firefox 157 | Firefox 157 |
| mozilla | firefox | < 157.0.0 | 157.0.0 |
| mozilla | firefox | >= 115.1.0 < 115.42.0 | 115.42.0 |
| mozilla | firefox | >= 140.0 < 140.17.0 | 140.17.0 |
| mozilla | firefox | >= 153.0 < 153.4.0 | 153.4.0 |
| mozilla | firefox_esr | < Firefox ESR 140.17 | Firefox ESR 140.17 |
| mozilla | firefox_esr | < Firefox ESR 153.4 | Firefox ESR 153.4 |
| mozilla | firefox_esr | < Firefox ESR 115.42 | Firefox ESR 115.42 |
| mozilla | thunderbird | < Thunderbird 140.17 | Thunderbird 140.17 |
| mozilla | thunderbird | < Thunderbird 157 | Thunderbird 157 |
| mozilla | thunderbird | < Thunderbird 153.4 | Thunderbird 153.4 |
| mozilla | thunderbird | < 157.0 | 157.0 |
| mozilla | thunderbird | >= 140.0 < 140.17.0 | 140.17.0 |
| mozilla | thunderbird | >= 153.0 < 153.4.0 | 153.4.0 |
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Mozilla
Mozilla Foundation Security Advisory 2026-102: CVE-2026-100781
vendor_mozilla
CVE-2026-100781 Mozilla Foundation Security Advisory 2026-102: CVE-2026-100781
Mozilla Foundation Security Advisory 2026-102
CVE: CVE-2026-100781
Product: Thunderbird
Impact: moderate
Fixed in: Thunderbird 140.17
Mozilla
Mozilla Foundation Security Advisory 2026-97: CVE-2026-100781
vendor_mozilla
CVE-2026-100781 Mozilla Foundation Security Advisory 2026-97: CVE-2026-100781
Mozilla Foundation Security Advisory 2026-97
CVE: CVE-2026-100781
Product: Firefox
Impact: low
Fixed in: Firefox 157
Mozilla
Mozilla Foundation Security Advisory 2026-101: CVE-2026-100781
vendor_mozilla
CVE-2026-100781 Mozilla Foundation Security Advisory 2026-101: CVE-2026-100781
Mozilla Foundation Security Advisory 2026-101
CVE: CVE-2026-100781
Product: Thunderbird
Impact: low
Fixed in: Thunderbird 157
Mozilla
Mozilla Foundation Security Advisory 2026-99: CVE-2026-100781
vendor_mozilla
CVE-2026-100781 Mozilla Foundation Security Advisory 2026-99: CVE-2026-100781
Mozilla Foundation Security Advisory 2026-99
CVE: CVE-2026-100781
Product: Firefox ESR
Impact: moderate
Fixed in: Firefox ESR 140.17
Mozilla
Mozilla Foundation Security Advisory 2026-103: CVE-2026-100781
vendor_mozilla
CVE-2026-100781 Mozilla Foundation Security Advisory 2026-103: CVE-2026-100781
Mozilla Foundation Security Advisory 2026-103
CVE: CVE-2026-100781
Product: Thunderbird
Impact: low
Fixed in: Thunderbird 153.4
Mozilla
Mozilla Foundation Security Advisory 2026-100: CVE-2026-100781
vendor_mozilla
CVE-2026-100781 Mozilla Foundation Security Advisory 2026-100: CVE-2026-100781
Mozilla Foundation Security Advisory 2026-100
CVE: CVE-2026-100781
Product: Firefox ESR
Impact: low
Fixed in: Firefox ESR 153.4
Mozilla
Mozilla Foundation Security Advisory 2026-98: CVE-2026-100781
vendor_mozilla
CVE-2026-100781 Mozilla Foundation Security Advisory 2026-98: CVE-2026-100781
Mozilla Foundation Security Advisory 2026-98
CVE: CVE-2026-100781
Product: Firefox ESR
Impact: moderate
Fixed in: Firefox ESR 115.42
VulDB
Mozilla Firefox up to 115.41/140.16/153.3/156 WebRender privileges management (WID-SEC-2026-3654)
vuldb·2026-10-03·CVSS 9.6
CVE-2026-100781 [CRITICAL] Mozilla Firefox up to 115.41/140.16/153.3/156 WebRender privileges management (WID-SEC-2026-3654)
A vulnerability categorized as critical has been discovered in Mozilla Firefox up to 115.41/140.16/153.3/156. This affects an unknown function of the component WebRender. The manipulation results in improper privilege management.
This vulnerability is reported as CVE-2026-100781. The attack can be launched remotely. No exploit exists.
It is advisable to upgrade the affected component.
GHSA
Sandbox escape due to incorrect boundary conditions in the Graphics: WebRender component.
ghsa_unreviewed·2026-09-29
CVE-2026-100781 Sandbox escape due to incorrect boundary conditions in the Graphics: WebRender component.
Sandbox escape due to incorrect boundary conditions in the Graphics: WebRender 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.
No writeups or analysis indexed.
https://bugzilla.mozilla.org/show_bug.cgi?id=2068434https://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