Description
A security vulnerability in Thunderbird allowed malicious sites to use redirects to send credentialed requests to arbitrary endpoints on any site that had invoked the Storage Access API. This enabled potential Cross-Site Request Forgery attacks across origins. This vulnerability was fixed in Firefox 138 and Thunderbird 138.
Affected products
mozilla: firefox; mozilla: thunderbird
References3
- www.mozilla.org/security/advisories/mfsa2025-28/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2025-31/ Vendor Advisory
- bugzilla.mozilla.org/show_bug.cgi?id=1953521 Permissions Required
Metrics
- CVSS 3.1
-
6.5
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N - EPSS — exploit probability
- 0% percentile: 7 · as of 7 November 2026
- CWE
- CWE-352
Could this be exploited in your environment?
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