CVE-2026-41431
HIGH
MEDIUM
Priority: 0.02
BB Relevance:
51/100
Published: 2026-05-11
Modified: 2026-10-26
First seen: 2026-10-29
Status: active
Attack Surface
Network
No Interaction
Conf. Impact
Integ. Impact
Scope Change
CVSS Vector Breakdown
AV:
Network
AC:
High
PR:
High
UI:
None
S:
Changed
C:
High
I:
High
A:
High
Description
Zen is a firefox-based browser. Prior to 1.19.9b, Zen Browser ships a Mozilla Application Resource (MAR) updater (org.mozilla.updater) that has had all MAR signature verification stripped from the Firefox codebase it was forked from. The MAR files served to users contain zero cryptographic signatures, and the updater binary contains zero cryptographic verification code. This eliminates the defense-in-depth that MAR signing provides. If the update server or GitHub release pipeline is compromised, arbitrary unsigned code can be delivered to all Zen users via the auto-update mechanism. This vulnerability is fixed in 1.19.9b.