cve.bz

CVE-2026-27587

7.7 highEPSS 0.4%

High (7.7) in caddyserver caddy. EPSS 0.4% chance of exploitation in the next 30 days. Fixed in github.com/caddyserver/caddy/v2 2.11.1.

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

CVSS 4.0

7.7 high
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:P

CVSS 3.1

9.1 critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
EPSS
0.4% chance of exploitation in the next 30 days; higher than 36% of CVEs (scores of 2026-10-31)
CWE
CWE-178
Published
Modified
Record from
the NVD, synced

Affected

Packages (OSV)

AdvisoryEcosystemPackageAffectedFixed in
GHSA-g7pc-pc7g-h8jhGogithub.com/caddyserver/caddy/v2<2.11.12.11.1
GO-2026-4538Gogithub.com/caddyserver/caddy/v2<2.11.12.11.1

References

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