CVE-2026-27585

EUVD-2026-8539
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.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
6.5 MEDIUM
NETWORK
LOW
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
Base Score
CVSS 3.x
EPSS Score
Percentile: 25.32%
Affected Products (NVD)
VendorProductVersion
caddyservercaddy
𝑥
< 2.11.1
𝑥
= Vulnerable software versions
Debian logo
Debian Releases
Debian Product
Codename
caddy
bookworm
vulnerable
forky
2.11.4-1
fixed
sid
2.11.4-1
fixed
trixie
vulnerable
trixie (security)
2.6.2-12+deb13u1
fixed
Ubuntu logo
Ubuntu Releases
Ubuntu Product
Codename
caddy
jammy
dne
noble
needs-triage
questing
ignored
resolute
needs-triage
Common Weakness Enumeration
References
https://github.com/caddyserver/caddy/blob/68d50020eef0d4c3398b878f17c8092ca5b58ca0/modules/caddyhttp/fileserver/matcher.go#L361
https://github.com/caddyserver/caddy/blob/68d50020eef0d4c3398b878f17c8092ca5b58ca0/modules/caddyhttp/fileserver/matcher.go#L398
https://github.com/caddyserver/caddy/releases/tag/v2.11.1
https://github.com/caddyserver/caddy/security/advisories/GHSA-4xrr-hq4w-6vf4