{"cve":"CVE-2026-77281","nvd":{"published":"2026-09-17T21:17:37.890","modified":"2026-09-24T21:16:28.120","status":"Awaiting Analysis","description":"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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L","score":6.5},"cwes":["CWE-94","CWE-178","CWE-770"],"references":["https://github.com/caddyserver/caddy/commit/176b043b0104cee3f894023cd5a598ac29e404bb","https://github.com/caddyserver/caddy/pull/7761","https://github.com/caddyserver/caddy/releases/tag/v2.11.4","https://github.com/caddyserver/caddy/security/advisories/GHSA-j8px-rmrx-76h9"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:55:23.253742848+00:00"},"epss":{"cve":"CVE-2026-77281","score":0.00491,"percentile":0.42229,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-j8px-rmrx-76h9","url":"https://osv.dev/vulnerability/GHSA-j8px-rmrx-76h9","summary":"Caddy: rewrite placeholder re-expansion, unbounded body buffer DoS, and fileHidden case-sensitivity bypass","modified":"2026-10-03T05:30:03.692995897Z","packages":[{"ecosystem":"Go","name":"github.com/caddyserver/caddy/v2","purl":"pkg:golang/github.com/caddyserver/caddy/v2","ranges":["<2.11.4"],"fixed":["2.11.4"]}]},{"id":"GO-2026-6512","url":"https://osv.dev/vulnerability/GO-2026-6512","summary":"Vulnerabilities in handler/placeholder layer in github.com/caddyserver/caddy","modified":"2026-10-01T20:55:47.886275070Z","packages":[{"ecosystem":"Go","name":"github.com/caddyserver/caddy/v2","purl":"pkg:golang/github.com/caddyserver/caddy/v2","ranges":["<2.11.4"],"fixed":["2.11.4"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}