CVE-2026-52844
Caddy: Windows `file_server` path authorization bypass via encoded backslash
7.5
HIGH
CVSS 3.1
EPSS 0.41%
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.
How to fix CVE-2026-52844
To remediate CVE-2026-52844, upgrade the affected package to a fixed version below.
- —no fix listed
- —upgrade to 2.11.4 or later
Is CVE-2026-52844 being exploited?
Low — EPSS is 0.4%, meaning exploitation activity has not been observed at scale.
Affected packages (2)
- from 0, <= 1.0.5
- from 0, < 2.11.4
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | HIGH7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N |