Home/CVE/Caddy is an extensible server platform that uses TLS by default. From version 2.7.5 to before version 2.11.2, the vars_r
CVE

CVE-2026-30852

Caddy is an extensible server platform that uses TLS by default. From version 2.7.5 to before version 2.11.2, the vars_r

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.

HIGH · CVSS 7.5 EPSS 0.00021
Act now
  • Public exploit or PoC is available
  • SSVC automatable: yes - attacks can be scripted at scale
  • CVSS base score ≥ 7.0
Sigma rules0 YARA rules0
⬡

Weakness Classification

CWE-200Exposure of Sensitive Information to an Unauthorized Actor
CWE-74Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')
▤

Affected Products & Versions

1
caddyserver caddy>= 2.7.5 and < 2.11.2
▤

Affected Packages

2
Language-ecosystem packages (from OSV) tied to this CVE, with the version that fixes it - the dependency-level detail NVD doesn’t carry.
Go github.com/caddyserver/caddy/v2 fixed in 2.11.2
Go github.com/caddyserver/caddy/v2/modules/caddyhttp MODERATE fixed in 2.11.2
⚠

Public Exploits & PoCs

1
pocgithub.com · GHSA-m2w3-8f23-hxxfgithub.com
▣

Scoring & Timeline

7.5
HIGH · CVSS v3.1 · security-advisories@github.com
View on NVD
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
Published to NVD07 Mar 2026 · 05:15 PM
CVSS VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
SSVC triage · cisa-vulnrichment
Exploitation
poc
Automatable
yes
Technical impact
partial
SSVC asks the questions that actually drive patch urgency: is it being exploited, can attacks be automated, and how total is the impact.
🔗

References & Sources

2
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
https://github.com/caddyserver/caddy/pull/5408Issue TrackingPatch
https://github.com/caddyserver/caddy/releases/tag/v2.11.2ProductRelease Notes
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