CVE-2026-52844 PUBLISHED

Caddy: Windows `file_server` path authorization bypass via encoded backslash

Assigner: GitHub_M
Reserved: 08.06.2026 Published: 23.06.2026 Updated: 23.06.2026

Caddy is an extensible server platform that uses TLS by default. Prior to 2.11.4, on Windows, Caddy path matchers treat /private\secret.txt as outside /private/, but file_server later resolves the same request path as private\secret.txt on disk. An unauthenticated remote client can bypass Caddy path-scoped auth/deny routes protecting /private/. This vulnerability is fixed in 2.11.4.

Metrics

CVSS 3.1

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
CVSS Score: 7.5

Attack Vector	Network	Scope	Unchanged
Attack Complexity	Low	Confidentiality Impact	High
Privileges Required	None	Integrity Impact	None
User Interaction	None	Availability Impact	None

CVSS 3.1

Product Status

Vendor	caddyserver
Product	caddy
Versions	Version < 2.11.4 is affected

References

https://github.com/caddyserver/caddy/security/advisories/GHSA-qrp7-cvwr-j2c6

Problem Types

CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') CWE
CWE-284: Improper Access Control CWE