{"id":"CVE-2026-56285","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-56285","generatedAt":"2026-10-28T02:14:02.611Z","title":"Nitter's /video media proxy endpoint fails to validate target URLs against Twitter/X domains and uses a hardcoded default HMAC key, allowing unauthenticated attackers to compute valid HMACs for arbitrary URLs.","description":"Nitter's /video media proxy endpoint fails to validate target URLs against Twitter/X domains and uses a hardcoded default HMAC key, allowing unauthenticated attackers to compute valid HMACs for arbitrary URLs. Attackers can retrieve HTTP responses from any host reachable by the server, including cloud metadata services and internal network resources.","published":"2026-06-29T18:16:38.000Z","lastModified":"2026-10-25T21:10:01.000Z","status":"Deferred","sourceIdentifier":"disclosure@vulncheck.com","cvss":{"version":"4.0","score":7.7,"severity":"HIGH","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:H/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M"},"cwe":["CWE-918","CWE-1188"],"affected":[],"epss":{"score":0.00462,"percentile":0.39811,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (0.46%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://github.com/zedeus/nitter/commit/44b2f096f67da2cc257a0e262a94a7ae79e95d47","source":"disclosure@vulncheck.com"},{"url":"https://github.com/zedeus/nitter/issues/1411","source":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/nitter-server-side-request-forgery-in-video-media-proxy-endpoint","source":"disclosure@vulncheck.com"},{"url":"https://github.com/zedeus/nitter/issues/1411","source":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-56285","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}