9.8

CVE-2025-11721: mozilla firefox

CVSS: 9.8v3.1CriticalModified
AliasesUBUNTU-CVE-2025-11721CGA-24r4-p8xx-m3cpCGA-5542-hqx7-w4pw
Published 14-10-2025Last modified 13-04-2026
Open JSON

Vulnerability summary

CVE-2025-11721 is a critical (CVSS 9.8) vulnerability in mozilla firefox. EPSS estimates a 0.36% chance of exploitation in the next 30 days, higher than 29% of scored vulnerabilities.

Overall risk
70/100
0100
High · default modelHow is this calculated?
CVSS score
9.8/10
010
Critical · v3.1 (CVE.org)
EPSS score
0.36%
0%100%
Low · 0.00 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-2025:15645-1OPENSUSE-SU-2026:11373-1CGA-RGJ9-558R-PVGM

Timeline

  1. 14-10-2025
    PublishedVulnerability first disclosed.
  2. 13-04-2026
    Last modifiedVulnerability information updated.

Description

Memory safety bug present in Firefox 143 and Thunderbird 143. This bug showed evidence of memory corruption and we presume that with enough effort this could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 144 and Thunderbird 144.

CVSS metrics

3 scores · 3 sources · 1 version

EPSS trend

Probability

0.36%

Chance of exploitation in the next 30 days

Percentile

29%

Versus all other CVEs

30-day change

0.00 pp

From 0.36% on 21-09-2026

21-09-202621-10-2026
EPSS score
0.36%

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

Ubuntu7 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< 144.0-r0
Wolfi1 product
  • firefox< 144.0-r0

4 vendors · 11 products

References

6 links