CVE-2026-16396

HIGH

Mozilla Firefox - Privilege Escalation in WebExtensions

Title source: rule
STIX 2.1

Description

Privilege escalation in WebExtensions. This vulnerability was fixed in Firefox 153, Firefox ESR 140.13, Thunderbird 153, and Thunderbird 140.13.

References (5)

Core 5

Scores

CVSS v3 8.8
EPSS 0.0024
EPSS Percentile 15.3%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact total

Details

CWE
CWE-269
Status published
Products (7)
mozilla/firefox < 140.13.0
mozilla/firefox < 153.0.0
Mozilla/Firefox 140.13 - 140.*
Mozilla/Firefox 153
mozilla/thunderbird < 140.13.0
Mozilla/Thunderbird 140.13 - 140.*
Mozilla/Thunderbird 153
Published Jul 21, 2026
Tracked Since Jul 21, 2026