CVE-2026-109739
published 2026-10-13CVE-2026-109739: Privilege escalation in the WebExtensions component. This vulnerability was fixed in Firefox 158 and Thunderbird 158.
PriorityP353high8.8CVSS 3.1
AVNACLPRLUINSUCHIHAH
EPSS
0.37%
30.5th percentile
Privilege escalation in the WebExtensions component. This vulnerability was fixed in Firefox 158 and Thunderbird 158.
Affected
2 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| mozilla | firefox | < Firefox 158 | Firefox 158 |
| mozilla | thunderbird | < Thunderbird 158 | Thunderbird 158 |
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Mozilla
Mozilla Foundation Security Advisory 2026-106: CVE-2026-109739
vendor_mozilla
CVE-2026-109739 Mozilla Foundation Security Advisory 2026-106: CVE-2026-109739
Mozilla Foundation Security Advisory 2026-106
CVE: CVE-2026-109739
Product: Firefox
Impact: low
Fixed in: Firefox 158
Mozilla
Mozilla Foundation Security Advisory 2026-109: CVE-2026-109739
vendor_mozilla
CVE-2026-109739 Mozilla Foundation Security Advisory 2026-109: CVE-2026-109739
Mozilla Foundation Security Advisory 2026-109
CVE: CVE-2026-109739
Product: Thunderbird
Impact: low
Fixed in: Thunderbird 158
GHSA
Privilege escalation in the WebExtensions component.
ghsa_unreviewed·2026-10-13
CVE-2026-109739 Privilege escalation in the WebExtensions component.
Privilege escalation in the WebExtensions component. This vulnerability was fixed in Firefox 158.
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2026-10-13
Published