CVE-2026-27585

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 v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/caddyserver/caddy/blob/68d50020eef0d4c3398b878f17c8092ca5b58ca0/modules/caddyhttp/fileserver/matcher.go#L361	Product
https://github.com/caddyserver/caddy/blob/68d50020eef0d4c3398b878f17c8092ca5b58ca0/modules/caddyhttp/fileserver/matcher.go#L398	Product
https://github.com/caddyserver/caddy/releases/tag/v2.11.1	Release Notes
https://github.com/caddyserver/caddy/security/advisories/GHSA-4xrr-hq4w-6vf4	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:caddyserver:caddy:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-02-24 17:29

Updated : 2026-02-25 17:13

NVD link : CVE-2026-27585

Mitre link : CVE-2026-27585

CVE.ORG link : CVE-2026-27585

JSON object : View

Products Affected

caddyserver

caddy

CWE

CWE-20

Improper Input Validation

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