CVE-2026-52844

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

Published Jun 23, 2026 CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed
Description
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-qrp7-cvwr-j2c6 Caddy: Windows `file_server` path authorization bypass via encoded backslash
History
Type Values Removed Values Added
First Time appeared Caddyserver
Caddyserver caddy
Vendors & Products Caddyserver
Caddyserver caddy
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description 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.
Title Caddy: Windows `file_server` path authorization bypass via encoded backslash
Weaknesses CWE-22
CWE-284
References
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Jun 23, 2026, 8:06 PM
Reserved
Jun 8, 2026, 6:41 PM
Status
Analyzed
Published
Jun 23, 2026, 6:18 PM
Modified
Oct 25, 2026, 11:10 PM