{"id":"CVE-2026-45135","aliases":["GHSA-m675-2p33-xv9g","GO-2026-5492"],"url":"https://o3.security/vulnerability/CVE-2026-45135","summary":"Caddy: Unsafe Unicode Handling in FastCGI splitPos Allows Execution of Non-PHP Files","details":"Caddy is an extensible server platform that uses TLS by default. From 2.7.0 until 2.11.3, the FastCGI transport's splitPos() in modules/caddyhttp/reverseproxy/fastcgi/fastcgi.go misuses golang.org/x/text/search with search.IgnoreCase when the request path contains a non-ASCII byte. Two distinct flaws in that fallback let an attacker mislead Caddy's FastCGI splitting into treating a non-.php (or other configured split_path extension) file as a script. In any deployment where the attacker can place content into a file served via FastCGI (uploads, file storage, etc.), this can be escalated to remote code execution by crafting a URL whose path triggers either flaw. This vulnerability is fixed in 2.11.3.","published":"2026-06-23T17:56:42.662Z","modified":"2026-08-12T03:51:35.985465039Z","cvss":{"score":8.1,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H"},"epss":{"score":0.00501,"percentile":0.40186,"asOf":"2026-08-10"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Go","name":"github.com/caddyserver/caddy/v2","fixedVersion":"2.11.3"}],"fix":null,"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/45xxx/CVE-2026-45135.json"},{"type":"ADVISORY","url":"https://github.com/caddyserver/caddy/security/advisories/GHSA-m675-2p33-xv9g"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-45135"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:35.985465039Z"}}