10

CVE-2026-0881: mozilla firefox Improper Access Control

CVSS: 10.0v3.1CriticalModified
AliasesUBUNTU-CVE-2026-0881CGA-73c4-cf87-wfcqCGA-wxhp-96r2-cjwg
Published 13-01-2026Last modified 15-07-2026
Open JSON

Vulnerability summary

CVE-2026-0881 is a critical (CVSS 10.0) Improper Access Control vulnerability in mozilla firefox. EPSS estimates a 0.35% chance of exploitation in the next 30 days, higher than 27.1% of scored vulnerabilities.

Overall risk
70/100
0100
High · default modelHow is this calculated?
CVSS score
10.0/10
010
Critical · v3.1 (CVE.org)
EPSS score
0.35%
0%100%
Low · -0.01 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 2 · Related 3
OPENSUSE-SU-2026:10046-1OPENSUSE-SU-2026:11373-1CGA-HW73-V752-243R

Timeline

  1. 13-01-2026
    PublishedVulnerability first disclosed.
  2. 15-07-2026
    Last modifiedVulnerability information updated.

Description

Sandbox escape in the Messaging System component. This vulnerability was fixed in Firefox 147 and Thunderbird 147.

CVSS metrics

3 scores · 3 sources · 1 version

EPSS trend

Probability

0.35%

Chance of exploitation in the next 30 days

Percentile

27%

Versus all other CVEs

30-day change

-0.01 pp

From 0.36% on 21-09-2026

21-09-202621-10-2026
EPSS score
0.35%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

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)
Mozilla2 products
Chainguard1 product
  • firefox< 147-r0
Wolfi1 product
  • firefox< 147-r0

4 vendors · 12 products

References

9 links