9.1

CVE-2026-16394: Mitigation bypass in the DOM: Security component

Modified
AliasesUBUNTU-CVE-2026-16394CGA-6jm8-cwx2-2rxhCGA-992f-r46g-r329
Published 21-07-2026Last modified 22-07-2026

Vulnerability summary

CVE-2026-16394 is a critical (CVSS 9.1) Protection Mechanism Failure vulnerability in mozilla firefox. EPSS estimates a 0.25% chance of exploitation in the next 30 days, higher than 15.4% of scored vulnerabilities.

Overall risk
70/100
0100
High · default modelHow is this calculated?
CVSS score
9.1/10
010
Critical · v3.1 (CVE.org)
EPSS score
0.25%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 8 · Related 9

Timeline

  1. 21-07-2026
    PublishedVulnerability first disclosed.
  2. 22-07-2026
    Last modifiedVulnerability information updated.

Description

Mitigation bypass in the DOM: Security component. This vulnerability was fixed in Firefox 153 and Thunderbird 153.

CVSS metrics

3 scores · 3 sources · 1 version

EPSS trend

Probability

0.25%

Chance of exploitation in the next 30 days

Percentile

15%

Versus all other CVEs

30-day change

No change 0.00 pp

From 0.25% on 22-09-2026

22-09-202622-10-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Ubuntu8 products
  • mozjs102All versions (No fix recorded)
  • mozjs115All versions (No fix recorded)
  • mozjs38All versions (No fix recorded)
  • mozjs52All versions (No fix recorded)
  • mozjs68All versions (No fix recorded)
Chainguard2 products
  • firefox< 153.0-r0
  • firefox-docker-selenium-compat< 153.0-r0
Wolfi2 products
  • firefox< 153.0-r0
  • firefox-docker-selenium-compat< 153.0-r0
Mozilla1 product

4 vendors · 13 products

References

6 links