{"id":"CVE-2026-77281","sourceIdentifier":"security-advisories@github.com","published":"2026-09-17T21:17:37.890","lastModified":"2026-09-24T21:16:28.120","vulnStatus":"Awaiting Analysis","cveTags":[],"descriptions":[{"lang":"en","value":"Caddy is an extensible server platform that uses TLS by default. In version 2.11.3 and earlier, three configuration-dependent weaknesses affect the handler and placeholder layer. In modules/caddyhttp/rewrite/rewrite.go, Rewrite.Rewrite() can pass attacker-controlled replacement bytes through buildQueryString for a second placeholder expansion when a rewrite URI ends with a literal question mark, allowing injected environment or request-variable placeholders to disclose data and, when the file provider is registered, allowing injected file placeholders to disclose readable files. The  issue is fixed in version 2.11.4."}],"affected":[{"source":"security-advisories@github.com","affectedData":[{"vendor":"caddyserver","product":"caddy","versions":[{"version":"< 2.11.4","status":"affected"}]}]}],"metrics":{"cvssMetricV31":[{"source":"security-advisories@github.com","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L","baseScore":6.5,"baseSeverity":"MEDIUM","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"LOW","integrityImpact":"NONE","availabilityImpact":"LOW"},"exploitabilityScore":3.9,"impactScore":2.5}],"ssvcV203":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","ssvcData":{"timestamp":"2026-09-18T14:39:55.254322Z","id":"CVE-2026-77281","options":[{"exploitation":"none"},{"automatable":"yes"},{"technicalImpact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}]},"weaknesses":[{"source":"security-advisories@github.com","type":"Secondary","description":[{"lang":"en","value":"CWE-94"},{"lang":"en","value":"CWE-178"},{"lang":"en","value":"CWE-770"}]}],"references":[{"url":"https://github.com/caddyserver/caddy/commit/176b043b0104cee3f894023cd5a598ac29e404bb","source":"security-advisories@github.com"},{"url":"https://github.com/caddyserver/caddy/pull/7761","source":"security-advisories@github.com"},{"url":"https://github.com/caddyserver/caddy/releases/tag/v2.11.4","source":"security-advisories@github.com"},{"url":"https://github.com/caddyserver/caddy/security/advisories/GHSA-j8px-rmrx-76h9","source":"security-advisories@github.com"}]}