6.1

CVE-2025-6430: mozilla firefox Cross-site Scripting

CVSS: 6.1v3.1MediumModified
AliasesUBUNTU-CVE-2025-6430DEBIAN-CVE-2025-6430CGA-qj87-6c6g-448x
Published 24-06-2025Last modified 13-04-2026
Open JSON

Vulnerability summary

CVE-2025-6430 is a medium (CVSS 6.1) Cross-site Scripting vulnerability in mozilla firefox. EPSS estimates a 0.27% chance of exploitation in the next 30 days, higher than 17.7% of scored vulnerabilities.

Overall risk
24/100
0100
Low · default modelHow is this calculated?
CVSS score
6.1/10
010
Medium · v3.1 (CVE.org)
EPSS score
0.27%
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 41 · Related 15
DLA-4231-1DLA-4239-1DSA-5950-1DSA-5959-1MGASA-2025-0201MGASA-2025-0228

Timeline

  1. 24-06-2025
    PublishedVulnerability first disclosed.
  2. 13-04-2026
    Last modifiedVulnerability information updated.

Description

When a file download is specified via the `Content-Disposition` header, that directive would be ignored if the file was included via a `<embed>` or `<object>` tag, potentially making a website vulnerable to a cross-site scripting attack. This vulnerability was fixed in Firefox 140, Firefox ESR 128.12, Thunderbird 140, and Thunderbird 128.12.

CVSS metrics

6 scores · 6 sources · 1 version

EPSS trend

Probability

0.27%

Chance of exploitation in the next 30 days

Percentile

18%

Versus all other CVEs

30-day change

+0.02 pp

From 0.25% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.27%

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< 128.12-r0
  • firefox-esr< 128.12-r0
Debian2 products
  • firefox-esr< 128.12.0esr-1~deb12u1 | < 128.12.0esr-1
  • thunderbird< 1:128.12.0esr-1~deb12u1 | < 1:128.12.0esr-1
Mozilla1 product
Wolfi1 product
  • firefox< 128.12-r0

5 vendors · 14 products

References

13 links
Show all 13 references