CVE-2026-30851

Caddy forward_auth copy_headers Does Not Strip Client-Supplied Headers, Allowing Identity Injection and Privilege Escalation

HIGH
8.8
CVSS Score
Published: March 7, 2026 at 04:28 PM UTC
Updated: June 17, 2026 at 10:33 AM UTC
1 product affected across 1 vendorCaddy

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Severity
HIGH8.8
Exploit prediction
EPSS 0.3%
SSVC
PoC

Description

Caddy is an extensible server platform that uses TLS by default. From version 2.10.0 to before version 2.11.2, forward_auth copy_headers does not strip client-supplied headers, allowing identity injection and privilege escalation. This issue has been patched in version 2.11.2.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 2.11.22.10.0 ≤ v < 2.11.2
Affected range stops below 2.11.2, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (4)

x_refsource_CONFIRMExploitMitigationPatchVendor Advisory
Source: cverecord
https://github.com/caddyserver/caddy/security/advisories/GHSA-7r4p-vjf4-gxv4
x_refsource_MISCIssue Tracking
Source: cverecord
https://github.com/caddyserver/caddy/issues/6610
x_refsource_MISCIssue TrackingPatch
Source: cverecord
https://github.com/caddyserver/caddy/pull/6608
x_refsource_MISCIssue TrackingPatch
Source: cverecord
https://github.com/caddyserver/caddy/pull/7545

SSVC — Action Prioritization

SSVCPoCNot automatableTotal impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH
Vector?

Quick Info

StatusANALYZED
CWE
CWE-287CWE-345

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