CVE-2026-27589

Caddy vulnerable to cross-origin config application via local admin API /load (caddy)

MEDIUM
6.5
CVSS Score
Published: February 24, 2026 at 04:30 PM UTC
Updated: June 17, 2026 at 10:27 AM UTC
1 product affected across 1 vendorCaddy

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Severity
MEDIUM6.5
Exploit prediction
EPSS 0.2%
SSVC
PoC

Description

Caddy is an extensible server platform that uses TLS by default. Prior to version 2.11.1, the local caddy admin API (default listen `127.0.0.1:2019`) exposes a state-changing `POST /load` endpoint that replaces the entire running configuration. When origin enforcement is not enabled (`enforce_origin` not configured), the admin endpoint accepts cross-origin requests (e.g., from attacker-controlled web content in a victim browser) and applies an attacker-supplied JSON config. This can change the admin listener settings and alter HTTP server behavior without user intent. Version 2.11.1 contains a fix for the issue.

Affected

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

v < 2.11.1
Affected range stops below 2.11.1, 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_CONFIRMExploitMitigationVendor Advisory
Source: cverecord
https://github.com/caddyserver/caddy/security/advisories/GHSA-879p-475x-rqh2
x_refsource_MISCRelease Notes
Source: cverecord
https://github.com/caddyserver/caddy/releases/tag/v2.11.1
x_refsource_MISCExploit
Source: cverecord
https://github.com/user-attachments/files/25079818/poc.zip
x_refsource_MISCExploitThird Party Advisory
Source: cverecord
https://github.com/user-attachments/files/25079820/PR_DESCRIPTION.md

SSVC — Action Prioritization

SSVCPoCNot automatablePartial impact

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

CVSS

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

Quick Info

StatusANALYZED
CWE
CWE-352

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