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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2025-6429 Detail

Current Description

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 affects Firefox < 140, Firefox ESR < 128.12, Thunderbird < 140, and Thunderbird < 128.12.


View Analysis Description

Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://bugzilla.mozilla.org/show_bug.cgi?id=1970658 Mozilla Corporation Permissions Required 
https://www.mozilla.org/security/advisories/mfsa2025-51/ Mozilla Corporation Vendor Advisory 
https://www.mozilla.org/security/advisories/mfsa2025-53/ Mozilla Corporation Vendor Advisory 
https://www.mozilla.org/security/advisories/mfsa2025-54/ Mozilla Corporation
https://www.mozilla.org/security/advisories/mfsa2025-55/ Mozilla Corporation

Weakness Enumeration

CWE-ID CWE Name Source
CWE-116 Improper Encoding or Escaping of Output CISA-ADP  

Known Affected Software Configurations Switch to CPE 2.2

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Change History

4 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2025-6429
NVD Published Date:
06/24/2025
NVD Last Modified:
07/14/2025
Source:
Mozilla Corporation