5.4

CVE-2026-2804: mozilla firefox Use After Free

CVSS: 5.4v3.1MediumModified
AliasesUBUNTU-CVE-2026-2804CGA-6qp9-q97w-48mgCGA-7mhj-p37w-h4mr
Published 24-02-2026Last modified 13-04-2026
Open JSON

Vulnerability summary

CVE-2026-2804 is a medium (CVSS 5.4) Use After Free vulnerability in mozilla firefox. EPSS estimates a 0.29% chance of exploitation in the next 30 days, higher than 20.9% of scored vulnerabilities.

Overall risk
22/100
0100
Low · default modelHow is this calculated?
CVSS score
5.4/10
010
Medium · v3.1 (CVE.org)
EPSS score
0.29%
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-2026:10257-1OPENSUSE-SU-2026:11373-1CGA-667V-QFPV-6H5H

Timeline

  1. 24-02-2026
    PublishedVulnerability first disclosed.
  2. 13-04-2026
    Last modifiedVulnerability information updated.

Description

Use-after-free in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 148 and Thunderbird 148.

CVSS metrics

3 scores · 3 sources · 1 version

EPSS trend

Probability

0.29%

Chance of exploitation in the next 30 days

Percentile

21%

Versus all other CVEs

30-day change

+0.01 pp

From 0.29% on 21-09-2026

21-09-202621-10-2026
EPSS score
0.29%

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< 148.0-r0
Wolfi1 product
  • firefox< 148.0-r0

4 vendors · 12 products

References

6 links