CVE-2026-100809
published 2026-09-29CVE-2026-100809: Same-origin policy bypass in the DevTools component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 153.4, and Firefox 157.
PriorityP340high8.1CVSS 3.1
AVNACLPRNUIRSUCHIHAN
EPSS
0.15%
4.4th percentile
Same-origin policy bypass in the DevTools 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 2026-100: CVE-2026-100809
vendor_mozilla
CVE-2026-100809 Mozilla Foundation Security Advisory 2026-100: CVE-2026-100809
Mozilla Foundation Security Advisory 2026-100
CVE: CVE-2026-100809
Product: Firefox ESR
Impact: low
Fixed in: Firefox ESR 153.4
Mozilla
Mozilla Foundation Security Advisory 2026-101: CVE-2026-100809
vendor_mozilla
CVE-2026-100809 Mozilla Foundation Security Advisory 2026-101: CVE-2026-100809
Mozilla Foundation Security Advisory 2026-101
CVE: CVE-2026-100809
Product: Thunderbird
Impact: low
Fixed in: Thunderbird 157
Mozilla
Mozilla Foundation Security Advisory 2026-97: CVE-2026-100809
vendor_mozilla
CVE-2026-100809 Mozilla Foundation Security Advisory 2026-97: CVE-2026-100809
Mozilla Foundation Security Advisory 2026-97
CVE: CVE-2026-100809
Product: Firefox
Impact: low
Fixed in: Firefox 157
Mozilla
Mozilla Foundation Security Advisory 2026-103: CVE-2026-100809
vendor_mozilla
CVE-2026-100809 Mozilla Foundation Security Advisory 2026-103: CVE-2026-100809
Mozilla Foundation Security Advisory 2026-103
CVE: CVE-2026-100809
Product: Thunderbird
Impact: low
Fixed in: Thunderbird 153.4
GHSA
Same-origin policy bypass in the DevTools component.
ghsa_unreviewed·2026-09-29
CVE-2026-100809 Same-origin policy bypass in the DevTools component.
Same-origin policy bypass in the DevTools 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