Firefox Same-Op Policy Bypass in Networking:DNS (pre-153/140.13)
CVE-2026-16381 Published on July 21, 2026
Same-origin policy bypass in the Networking: DNS component
Same-origin policy bypass in the Networking: DNS component. This vulnerability was fixed in Firefox 153, Firefox ESR 140.13, Thunderbird 153, and Thunderbird 140.13.
Vulnerability Analysis
CVE-2026-16381 can be exploited with network access, and does not require authorization privileges or user interaction. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have a high impact on confidentiality and integrity, and no impact on availability.
Weakness Type
Origin Validation Error
The software does not properly verify that the source of data or communication is valid.
Products Associated with CVE-2026-16381
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Affected Versions
Mozilla Firefox:- Version 140.13, <= 140.* is unaffected.
- Version 153, <= * is unaffected.
- Version 140.13, <= 140.* is unaffected.
- Version 153, <= * is unaffected.