CVE-2026-27585: medium-severity vulnerability in caddyserver caddy
Caddy's improper sanitization of glob characters in file matcher may lead to bypassing security protections
Published · Updated
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 6.9epss 0.4%
Caddy is an extensible server platform that uses TLS by default. Prior to version 2.11.1, the path sanitization routine in file matcher doesn't sanitize backslashes which can lead to bypassing path related security protections. It affects users with specific Caddy and environment configurations. Version 2.11.1 fixes the issue.
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:P
Affected products
caddyserver · caddyRelated CVEs — caddyserver caddy
In the same product, most dangerous first.
CVE-2026-45135HIGHCaddy: Unsafe Unicode Handling in FastCGI splitPos Allows Execution of Non-PHP FilesEPSS 0.7%CVE-2026-52844HIGHCaddy: Windows `file_server` path authorization bypass via encoded backslashEPSS 0.6%CVE-2026-27590HIGHCaddy: Unicode case-folding length expansion causes incorrect split_path index (SCRIPT_NAME/PATH_INFO confusion) in FastCGI transportEPSS 0.6%CVE-2026-55458LOWCaddy: RFC 7230 §6.1 compliance issue / Hop-by-hop headers that leak throughEPSS 0.5%CVE-2026-77281MEDIUMCaddy: rewrite placeholder re-expansionEPSS 0.5%CVE-2026-30852MEDIUMCaddy: vars_regexp double-expands user input, leaking env vars and filesEPSS 0.5%
References
https://github.com/caddyserver/caddy/blob/68d50020eef0d4c3398b878f17c8092ca5b58ca0/modules/caddyhttp/fileserver/matcher.go#L361https://github.com/caddyserver/caddy/blob/68d50020eef0d4c3398b878f17c8092ca5b58ca0/modules/caddyhttp/fileserver/matcher.go#L398https://github.com/caddyserver/caddy/releases/tag/v2.11.1https://github.com/caddyserver/caddy/security/advisories/GHSA-4xrr-hq4w-6vf4