CVE-2026-8948: Same-origin policy bypass in Firefox DOM networking
CVE-2026-8948 Published on May 19, 2026
Same-origin policy bypass in the DOM: Networking component
Same-origin policy bypass in the DOM: Networking component. This vulnerability was fixed in Firefox 151 and Thunderbird 151.
Vulnerability Analysis
CVE-2026-8948 is exploitable 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
Permissive Cross-domain Policy with Untrusted Domains
The software uses a cross-domain policy file that includes domains that should not be trusted.
Products Associated with CVE-2026-8948
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Affected Versions
Mozilla Firefox:- Version 151, <= * is unaffected.
- Version 151, <= * is unaffected.
Exploit Probability
EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.