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TI-2025-05830 Aliases CVE-2025-6429GHSA-8r38-4g4q-hgvw

Incorrect parsing of URLs could have allowed embedding of youtube.com

Priority LOW 29CWE-116Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
Required
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
None · High · None
Fix status
Partial Red Hat: 14 fixed, 3 without a fix

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA and Red Hat.

Summary

Firefox could have incorrectly parsed a URL and rewritten it to the youtube.com domain when parsing the URL specified in an `embed` tag. This could have bypassed website security checks that restricted which domains users were allowed to embed. This vulnerability was fixed in Firefox 140, Firefox ESR 128.12, Thunderbird 140, and Thunderbird 128.12.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00355 29th percentileScored 2026-11-07
Fix Partial Firefox (Mozilla): 128.12, 140Thunderbird (Mozilla): 128.12, 140Red Hat: 21 advisoriesRed Hat: 14 fixed, 3 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
MozillaFirefox—128.12, 140Patch availableCNA
MozillaThunderbird—128.12, 140Patch availableCNA
  • Firefox VendorMozilla Affected — Fixed in 128.12, 140 Patch available CNA
  • Thunderbird VendorMozilla Affected — Fixed in 128.12, 140 Patch available CNA

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*before 128.12.0VulnerableMozilla
cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:*before 140.0VulnerableMozilla
  • cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:* Versions before 128.12.0 Vulnerable ·Mozilla
  • cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:* Versions before 140.0 Vulnerable ·Mozilla

Remediation

  • Fix · CNA Firefox (Mozilla) Fixed in 128.12, 140
  • Fix · CNA Thunderbird (Mozilla) Fixed in 128.12, 140

Red Hat 21 advisories

  • RHSA-2025:10246 Released 2025-07-02 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream (v. 8) thunderbird-128.12.0-1.el8_10
  • RHSA-2025:10196 Released 2025-07-02 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream (v. 9) thunderbird-128.12.0-1.el9_6
  • RHSA-2025:10195 Released 2025-07-02 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream (v. 10) thunderbird-128.12.0-1.el10_0
Show 18 more Red Hat advisories
  • RHSA-2025:10188 Released 2025-07-02 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream EUS (v.9.4) firefox-128.12.0-1.el9_4, firefox-x11-128.12.0-1.el9_4
  • RHSA-2025:10186 Released 2025-07-02 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream E4S (v.8.8) firefox-128.12.0-1.el8_8
    • Red Hat Enterprise Linux AppStream TUS (v.8.8) firefox-128.12.0-1.el8_8
  • RHSA-2025:10185 Released 2025-07-02 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.2) firefox-128.12.0-1.el9_2, firefox-x11-128.12.0-1.el9_2
  • RHSA-2025:10183 Released 2025-07-02 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream AUS (v.8.6) firefox-128.12.0-1.el8_6
    • Red Hat Enterprise Linux AppStream E4S (v.8.6) firefox-128.12.0-1.el8_6
    • Red Hat Enterprise Linux AppStream TUS (v.8.6) firefox-128.12.0-1.el8_6
  • RHSA-2025:10187 Released 2025-07-02 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.0) firefox-128.12.0-1.el9_0
  • RHSA-2025:10184 Released 2025-07-02 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream AUS (v.8.4) firefox-128.12.0-1.el8_4
  • RHSA-2025:10181 Released 2025-07-02 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux Server (v. 7 ELS) firefox-128.12.0-1.el7_9
  • RHSA-2025:10182 Released 2025-07-02 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream AUS (v. 8.2) firefox-128.12.0-1.el8_2
  • RHSA-2025:10072 Released 2025-07-01 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream (v. 9) firefox-128.12.0-1.el9_6, firefox-x11-128.12.0-1.el9_6
  • RHSA-2025:10164 Released 2025-07-01 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream AUS (v.8.6) thunderbird-128.12.0-1.el8_6
    • Red Hat Enterprise Linux AppStream E4S (v.8.6) thunderbird-128.12.0-1.el8_6
    • Red Hat Enterprise Linux AppStream TUS (v.8.6) thunderbird-128.12.0-1.el8_6
  • RHSA-2025:10073 Released 2025-07-01 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream (v. 10) firefox-128.12.0-1.el10_0
  • RHSA-2025:10159 Released 2025-07-01 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream EUS (v.9.4) thunderbird-128.12.0-1.el9_4
  • RHSA-2025:10160 Released 2025-07-01 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.2) thunderbird-128.12.0-1.el9_2
  • RHSA-2025:10163 Released 2025-07-01 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream E4S (v.8.8) thunderbird-128.12.0-1.el8_8
    • Red Hat Enterprise Linux AppStream TUS (v.8.8) thunderbird-128.12.0-1.el8_8
  • RHSA-2025:10165 Released 2025-07-01 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream AUS (v.8.4) thunderbird-128.12.0-1.el8_4
  • RHSA-2025:10161 Released 2025-07-01 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.0) thunderbird-128.12.0-1.el9_0
  • RHSA-2025:10166 Released 2025-07-01 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream AUS (v. 8.2) thunderbird-128.12.0-1.el8_2
  • RHSA-2025:10074 Released 2025-07-01 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream (v. 8) firefox-128.12.0-1.el8_10

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 10AffectedNo fix yet
Red Hat Enterprise Linux 6AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 7AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2025:10073, RHSA-2025:10195
Red Hat Enterprise Linux AppStream (v. 8)Fixed RHSA-2025:10074, RHSA-2025:10246
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2025:10072, RHSA-2025:10196
Red Hat Enterprise Linux AppStream AUS (v. 8.2)Fixed RHSA-2025:10166, RHSA-2025:10182
Red Hat Enterprise Linux AppStream AUS (v.8.4)Fixed RHSA-2025:10165, RHSA-2025:10184
Red Hat Enterprise Linux AppStream AUS (v.8.6)Fixed RHSA-2025:10164, RHSA-2025:10183
Red Hat Enterprise Linux AppStream E4S (v.8.6)Fixed RHSA-2025:10164, RHSA-2025:10183
Red Hat Enterprise Linux AppStream E4S (v.8.8)Fixed RHSA-2025:10163, RHSA-2025:10186
Red Hat Enterprise Linux AppStream E4S (v.9.0)Fixed RHSA-2025:10161, RHSA-2025:10187
Red Hat Enterprise Linux AppStream E4S (v.9.2)Fixed RHSA-2025:10160, RHSA-2025:10185
Red Hat Enterprise Linux AppStream EUS (v.9.4)Fixed RHSA-2025:10159, RHSA-2025:10188
Red Hat Enterprise Linux AppStream TUS (v.8.6)Fixed RHSA-2025:10164, RHSA-2025:10183
Red Hat Enterprise Linux AppStream TUS (v.8.8)Fixed RHSA-2025:10163, RHSA-2025:10186
Red Hat Enterprise Linux Server (v. 7 ELS)Fixed RHSA-2025:10181

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-6429
  2. 2026-10-03 Alias added: GHSA-8r38-4g4q-hgvw

References

Advisory 2

Other 3

  • TI-2024-08981 Use after free in Mozilla Firefox KEVCVSS 3.1CRITICAL 9.8
  • TI-2022-09832 Use after free in Mozilla Firefox KEVCVSS 3.1CRITICAL 9.6
  • TI-2019-08769 Improper input validation in Mozilla Firefox ESR KEVCVSS 3.1CRITICAL 10.0
  • TI-2010-03577 Mozilla Firefox 3.5.x through 3.5.14 and 3.6.x through 3.6.11, Thunderbird 3.1.6 before… KEVCVSS 3.1CRITICAL 9.8
  • TI-2023-04799 Out-of-bounds write in Google Chrome KEVCVSS 3.1HIGH 8.8
  • TI-2023-04477 Out-of-bounds write in Google Chrome KEVCVSS 3.1HIGH 8.8
See all 3444 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences