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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-30852 Detail

Description

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.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

Nist CVSS score does not match with CNA score
CNA:  GitHub, Inc.
CVSS-BT 5.5 MEDIUM
Vector:  CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:P

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://github.com/caddyserver/caddy/pull/5408 GitHub, Inc.
https://github.com/caddyserver/caddy/releases/tag/v2.11.2 GitHub, Inc.
https://github.com/caddyserver/caddy/security/advisories/GHSA-m2w3-8f23-hxxf GitHub, Inc.

Weakness Enumeration

CWE-ID CWE Name Source
CWE-74 Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection') GitHub, Inc.  
CWE-200 Exposure of Sensitive Information to an Unauthorized Actor GitHub, Inc.  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-30852
NVD Published Date:
03/07/2026
NVD Last Modified:
03/07/2026
Source:
GitHub, Inc.