CVE-2026-30852 (GCVE-0-2026-30852)
Vulnerability from cvelistv5
Published
2026-03-07 16:28
Modified
2026-03-09 18:24
CWE
  • CWE-200 - Exposure of Sensitive Information to an Unauthorized Actor
  • CWE-74 - Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')
Summary
Caddy is an extensible server platform that uses TLS by default. From version 2.7.5 to before version 2.11.2, the vars_regexp matcher in vars.go:337 double-expands user-controlled input through the Caddy replacer. When vars_regexp matches against a placeholder like {http.request.header.X-Input}, the header value gets resolved once (expected), then passed through repl.ReplaceAll() again (the bug). This means an attacker can put {env.DATABASE_URL} or {file./etc/passwd} in a request header and the server will evaluate it, leaking environment variables, file contents, and system info. This issue has been patched in version 2.11.2.
Impacted products
Vendor Product Version
caddyserver caddy Version: >= 2.7.5, < 2.11.2
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Show details on NVD website


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