CVE-2026-100787
published 2026-09-29CVE-2026-100787: Sandbox escape in the XUL component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 153.4, and Firefox 157.
PriorityP348critical9.6CVSS 3.1
AVNACLPRNUIRSCCHIHAH
EPSS
0.30%
21.0th percentile
Sandbox escape in the XUL component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 153.4, and Firefox 157.
Affected
8 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| mozilla | firefox | < Firefox 157 | Firefox 157 |
| mozilla | firefox | < 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 | thunderbird | < Thunderbird 157 | Thunderbird 157 |
| mozilla | thunderbird | < Thunderbird 153.4 | Thunderbird 153.4 |
| mozilla | thunderbird | < 153.4.0 | 153.4.0 |
| mozilla | thunderbird | >= 154.0 < 157.0 | 157.0 |
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Mozilla
Mozilla Foundation Security Advisory 2026-101: CVE-2026-100787
vendor_mozilla
CVE-2026-100787 Mozilla Foundation Security Advisory 2026-101: CVE-2026-100787
Mozilla Foundation Security Advisory 2026-101
CVE: CVE-2026-100787
Product: Thunderbird
Impact: low
Fixed in: Thunderbird 157
Mozilla
Mozilla Foundation Security Advisory 2026-103: CVE-2026-100787
vendor_mozilla
CVE-2026-100787 Mozilla Foundation Security Advisory 2026-103: CVE-2026-100787
Mozilla Foundation Security Advisory 2026-103
CVE: CVE-2026-100787
Product: Thunderbird
Impact: low
Fixed in: Thunderbird 153.4
Mozilla
Mozilla Foundation Security Advisory 2026-100: CVE-2026-100787
vendor_mozilla
CVE-2026-100787 Mozilla Foundation Security Advisory 2026-100: CVE-2026-100787
Mozilla Foundation Security Advisory 2026-100
CVE: CVE-2026-100787
Product: Firefox ESR
Impact: low
Fixed in: Firefox ESR 153.4
Mozilla
Mozilla Foundation Security Advisory 2026-97: CVE-2026-100787
vendor_mozilla
CVE-2026-100787 Mozilla Foundation Security Advisory 2026-97: CVE-2026-100787
Mozilla Foundation Security Advisory 2026-97
CVE: CVE-2026-100787
Product: Firefox
Impact: low
Fixed in: Firefox 157
GHSA
Sandbox escape in the XUL component.
ghsa_unreviewed·2026-09-29
CVE-2026-100787 Sandbox escape in the XUL component.
Sandbox escape in the XUL component. This vulnerability was fixed in Firefox ESR 153.4 and Firefox 157.
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2026-09-29
Published