Description
Caddy is an extensible server platform that uses TLS by default. Prior to version 2.11.1, Caddy's HTTP `host` request matcher is documented as case-insensitive, but when configured with a large host list (>100 entries) it becomes case-sensitive due to an optimized matching path. An attacker can bypass host-based routing and any access controls attached to that route by changing the casing of the `Host` header. Version 2.11.1 contains a fix for the issue.
Scores
CVSS v3
9.1
EPSS
0.0006
EPSS Percentile
18.5%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
CISA SSVC
Vulnrichment
Exploitation
poc
Automatable
yes
Technical Impact
partial
Details
CWE
CWE-178
Status
published
Products (2)
caddyserver/caddy
0 - 2.11.1Go
caddyserver/caddy
2.10.2 - 2.11.1
Published
Feb 24, 2026
Tracked Since
Feb 25, 2026