CVE-2026-53900

Firefox for iOS preserved cookies set on the initial PDF request across cross-origin HTTP redirects in TemporaryDocument, allowing a malicious site to inject arbitrary cookies into requests to an unrelated target domain. This vulnerability was fixed in Firefox for iOS 152.0...

Security Vulnerabilities fixed in Firefox for iOS 152.0 — Mozilla

Firefox for iOS used partial domain matching when attaching cookies to PDF requests, allowing a malicious site on a suffix domain to receive cookies belonging to the target site. Firefox for iOS preserved cookies set on the initial PDF request across cross-origin HTTP redirects in...