CVE-2026-30851 — HIGH (8.1)

Q: How severe is CVE-2026-30851?

CVE-2026-30851 has been rated HIGH with a CVSS base score of 8.1/10. Review the CVSS metrics above for detailed severity breakdown.

Q: Is there a patch for CVE-2026-30851?

Check the references section above for vendor advisories and patch information. Affected products include: Caddyserver Caddy.

Vulnerability 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.

CVSS Score

8.1

HIGH

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

LOW

User Interaction

NONE

Scope

UNCHANGED

Confidentiality

HIGH

Integrity

HIGH

Availability

NONE

Affected Products

Vendor	Product	Versions
Caddyserver	Caddy	>= 2.10.0, < 2.11.2

Related Weaknesses (CWE)

CWE-287 CWE-345

References

https://github.com/caddyserver/caddy/issues/6610Issue Tracking
https://github.com/caddyserver/caddy/pull/6608Issue TrackingPatch
https://github.com/caddyserver/caddy/pull/7545Issue TrackingPatch
https://github.com/caddyserver/caddy/security/advisories/GHSA-7r4p-vjf4-gxv4ExploitMitigationPatch

FAQ

What is CVE-2026-30851?

CVE-2026-30851 is a vulnerability with a CVSS score of 8.1 (HIGH). 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 injec...

How severe is CVE-2026-30851?

CVE-2026-30851 has been rated HIGH with a CVSS base score of 8.1/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-30851?

Check the references section above for vendor advisories and patch information. Affected products include: Caddyserver Caddy.