CVE-2026-16365 | BDVDB-2026-350232 Detail

MozillaFirefox

Description#

Privilege escalation in the DOM: Workers component. This vulnerability was fixed in Firefox 153, Thunderbird 153, Firefox ESR 140.15, and Thunderbird 140.15.

Impact#

Per CVSS v3.1: confidentiality impact high, integrity impact high, availability impact high. Attack vector: network.

Weaknesses#

CWE-269 Improper Privilege Management
CWE-284 Improper Access Control

References#

Exploit#

No public exploit known

History#

Version 12026-07-21Record published in the CVE List.
Version 22026-09-01Most recent update recorded in the CVE List.

Published

Published: 2026-07-21
Last modified: 2026-09-01

Vendor information

Vendor: Mozilla
Product: Firefox

All Mozilla vulnerabilities

Score

8.8 High

EPSS

less than 1%, Very Low

Estimated chance of exploitation in the next 30 days. EPSS percentile: 20.4.

KEV

Not listed in the CISA Known Exploited Vulnerabilities catalog.

Impact

Privilege Escalation

Action

No specific action is recorded in the source data. Check the references for vendor guidance.

Affected Systems

Vulnerable
Not stated
Fixed
140.15
Vulnerable
Not stated
Fixed
153

Scoring System

CVSS v4.0

Not available

CVSS v3.1

8.8 High

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Metric breakdown
Attack Vector	Network
Attack Complexity	Low
Privileges Required	None
User Interaction	Required
Scope	Unchanged
Confidentiality	High
Integrity	High
Availability	High

CVSS v3.0

Not available

CVSS v2

Not available

Source: CVE List v5 (record); CISA KEV (kev, action); FIRST EPSS (epss).