9.1

CVE-2025-4083: mozilla firefox

CVSS: 9.1v3.1CriticalModified
AliasesUBUNTU-CVE-2025-4083DEBIAN-CVE-2025-4083CGA-5w67-q8vg-8rwq
Published 29-04-2025Last modified 25-07-2026
Open JSON

Vulnerability summary

CVE-2025-4083 is a critical (CVSS 9.1) vulnerability in mozilla firefox. EPSS estimates a 0.45% chance of exploitation in the next 30 days, higher than 37.8% 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
0.45%
0%100%
Low · +0.02 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 34 · Related 7
DLA-4167-1DLA-4172-1DSA-5910-1DSA-5912-1MGASA-2025-0150MGASA-2025-0151

Timeline

  1. 29-04-2025
    PublishedVulnerability first disclosed.
  2. 25-07-2026
    Last modifiedVulnerability information updated.

Description

A process isolation vulnerability in Thunderbird stemmed from improper handling of javascript: URIs, which could allow content to execute in the top-level document's process instead of the intended frame, potentially enabling a sandbox escape. This vulnerability was fixed in Firefox 138, Firefox ESR 128.10, Firefox ESR 115.23, Thunderbird 138, and Thunderbird 128.10.

CVSS metrics

6 scores · 6 sources · 1 version

EPSS trend

Probability

0.45%

Chance of exploitation in the next 30 days

Percentile

38%

Versus all other CVEs

30-day change

+0.02 pp

From 0.43% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.45%

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)
Chainguard2 products
  • firefox< 128.10-r0
  • firefox-esr< 115.23-r0
Debian2 products
  • firefox-esr< 128.10.0esr-1~deb12u1 | < 128.10.0esr-1
  • thunderbird< 1:128.10.0esr-1~deb12u1 | < 1:128.10.0esr-1
Mozilla2 products
Wolfi1 product
  • firefox< 128.10-r0

5 vendors · 15 products

References

14 links
Show all 14 references