{"action":"Upgrade firefox-esr to 128.11.0esr-1~deb12u1 or later.","affected":[{"fixed":"128.11.0esr-1~deb12u1","introduced":"0"}],"component":"firefox-esr","cve_ids":[],"ecosystem":"Debian","ecosystem_qualifier":"Debian:12","exploited":false,"fixed_versions":["128.11.0esr-1~deb12u1"],"id":"tcs_01M5NP0F1FFJQVS8C5Z4F8SW0R","modified_at":"2026-10-06T09:47:34.661473846Z","published_at":"2025-05-27T13:15:22.403Z","references":["https://osv.dev/vulnerability/DEBIAN-CVE-2025-5266","https://security-tracker.debian.org/tracker/CVE-2025-5266"],"severity":{"label":"medium","score":4.3},"sources":[{"source":"osv","source_id":"DEBIAN-CVE-2025-5266","url":"https://osv.dev/vulnerability/DEBIAN-CVE-2025-5266"}],"summary":"Script elements loading cross-origin resources generated load and error events which leaked information enabling XS-Leaks attacks. This vulnerability was fixed in Firefox 139, Firefox ESR 128.11, Thun"}