{"id":"CVE-2026-54603","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-54603","generatedAt":"2026-10-28T09:42:28.455Z","title":"From 0.4.0 to 2.0.21, a protocol-relative redirect Location returned to OAuth2::Client#request overrides the request authority, so the bearer Authorization header is sent to an attacker-controlled host, leaking the credential.","description":"OAuth2 is a Ruby wrapper for the OAuth 2.0 and 2.1 authorization frameworks, including OpenID Connect (OIDC). From 0.4.0 to 2.0.21, a protocol-relative redirect Location returned to OAuth2::Client#request overrides the request authority, so the bearer Authorization header is sent to an attacker-controlled host, leaking the credential. This issue is fixed in version 2.0.22.","published":"2026-07-28T17:16:52.000Z","lastModified":"2026-10-23T23:10:00.000Z","status":"Awaiting Analysis","sourceIdentifier":"security-advisories@github.com","cvss":{"version":"3.1","score":8.6,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N"},"cwe":["CWE-200","CWE-601"],"affected":[],"epss":{"score":0.00448,"percentile":0.38792,"date":"2026-10-27","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 (0.45%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://github.com/ruby-oauth/oauth2/commit/0f0a474f1b38453e119e660c2daca742d4378ce9","source":"security-advisories@github.com"},{"url":"https://github.com/ruby-oauth/oauth2/releases/tag/v2.0.22","source":"security-advisories@github.com"},{"url":"https://github.com/ruby-oauth/oauth2/security/advisories/GHSA-pp92-crg2-gfv9","source":"security-advisories@github.com"},{"url":"https://lists.debian.org/debian-lts-announce/2026/10/msg00014.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/ruby-oauth/oauth2/security/advisories/GHSA-pp92-crg2-gfv9","source":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-54603","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."}