CVE-2026-27587 (GCVE-0-2026-27587)
Vulnerability from cvelistv5 – Published: 2026-02-24 16:26 – Updated: 2026-02-27 20:48
VLAI
EPSS
VEX
Title
Caddy: MatchPath %xx (escaped-path) branch skips case normalization, enabling path-based route/auth bypass
Summary
Caddy is an extensible server platform that uses TLS by default. Prior to version 2.11.1, Caddy's HTTP `path` request matcher is intended to be case-insensitive, but when the match pattern contains percent-escape sequences (`%xx`) it compares against the request's escaped path without lowercasing. An attacker can bypass path-based routing and any access controls attached to that route by changing the casing of the request path. Version 2.11.1 contains a fix for the issue.
Severity
SSVC
Exploitation: poc
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-02-27 20:47 UTC
CWE
- CWE-178 - Improper Handling of Case Sensitivity
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/caddyserver/caddy/security/adv… | x_refsource_CONFIRM |
| https://github.com/caddyserver/caddy/releases/tag… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| caddyserver | caddy |
Affected:
< 2.11.1
|
guessed |
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