CVE-2026-111322: Archon Auth Bypass Vulnerability

CVE-2026-111322 Overview

CVE-2026-111322 is a missing authentication vulnerability [CWE-306] in Archon versions 0.2.13 through 0.11.1. The /api/* control API binds to 0.0.0.0 by default and does not require authentication. Unauthenticated attackers with network access can send messages to the AI coding agent, which runs with bypassPermissions enabled. This allows arbitrary command execution on the host under the Archon user context. The flaw affects a self-hosted AI coding agent platform exposed on any accessible network interface.

Critical Impact
Unauthenticated network attackers can execute arbitrary commands on Archon hosts by abusing the exposed control API and the agent's bypassPermissions configuration.

Affected Products

Archon 0.2.13 (initial affected version)
Archon versions 0.2.13 through 0.11.1
Archon 0.11.1 (latest confirmed affected version)

Discovery Timeline

2026-10-15 - CVE-2026-111322 published to NVD
2026-10-16 - Last updated in NVD database

Technical Details for CVE-2026-111322

Vulnerability Analysis

Archon exposes an HTTP control API under the /api/* route tree. The server binds to 0.0.0.0, making the API reachable on every network interface by default. The authentication configuration in packages/server/src/auth/config.ts leaves protection disabled out of the box. API routes defined in packages/server/src/routes/api.ts accept requests without validating caller identity.

One of these endpoints forwards attacker-supplied messages to an internal AI coding agent. That agent is launched with bypassPermissions, which disables the agent's own guardrails for host operations. The result is a direct path from an unauthenticated HTTP request to command execution on the Archon host.

Root Cause

The root cause is missing authentication [CWE-306] on a privileged administrative API. The default binding of 0.0.0.0 combined with an agent configured to bypass permission prompts eliminates every layer of access control. See the HackMD Authentication Analysis and VulnCheck Advisory on Archon for the full analysis.

Attack Vector

The attack vector is network-based and requires no privileges or user interaction. An attacker locates an Archon instance reachable on TCP, submits a crafted request to the control API, and instructs the AI coding agent to run shell commands. Commands execute with the privileges of the Archon user. Relevant source references include the GitHub Auth Config Code, GitHub Server Index Code, and GitHub API Routes Code.

No verified proof-of-concept code is published. Technical details are available in the linked advisories.

Detection Methods for CVE-2026-111322

Indicators of Compromise

Unexpected inbound HTTP requests to /api/* endpoints on Archon hosts from untrusted sources.
Child processes spawned by the Archon user that match shell interpreters, package managers, or network utilities.
Outbound connections from the Archon host to attacker-controlled infrastructure immediately after API traffic.
New files, cron entries, or SSH keys created under the Archon user's home directory.

Detection Strategies

Audit all Archon deployments for the listening interface and confirm whether /api/* is reachable from untrusted networks.
Alert on any unauthenticated access to the control API in reverse proxy or load balancer logs.
Correlate HTTP request bursts to /api/* with subsequent process creation events on the host.
Monitor the AI coding agent process tree for unexpected command execution chains.

Monitoring Recommendations

Forward Archon server logs and host process telemetry to a centralized analytics platform for correlation.
Track egress from Archon hosts and baseline normal destinations to flag anomalies.
Enable file integrity monitoring on configuration files, including auth/config.ts and startup scripts.

How to Mitigate CVE-2026-111322

Immediate Actions Required

Remove direct network exposure of Archon by binding the service to 127.0.0.1 or an internal interface only.
Place Archon behind an authenticating reverse proxy that enforces identity on every /api/* request.
Disable bypassPermissions for the AI coding agent and require explicit approval for host operations.
Rotate credentials, tokens, and SSH keys reachable from any Archon host that was exposed.

Patch Information

At the time of publication, no fixed Archon release is listed in the NVD entry for versions after 0.11.1. Monitor the GitHub Project Repository and the VulnCheck Advisory on Archon for an official patched version. Apply vendor updates as soon as they are released.

Workarounds

Restrict access to the Archon host with host firewall rules allowing only trusted management IPs.
Terminate TLS and enforce authentication at an upstream proxy such as Nginx, Caddy, or an identity-aware access gateway.
Run Archon under a dedicated low-privilege system account with no sudo rights and minimal filesystem permissions.
Isolate Archon in a dedicated network segment or container with strict egress controls.

bash

# Example: block external access to the Archon API port (default 0.0.0.0 binding)
# Replace 8080 with the port used by your Archon deployment
sudo iptables -A INPUT -p tcp --dport 8080 -s 127.0.0.1 -j ACCEPT
sudo iptables -A INPUT -p tcp --dport 8080 -j DROP

# Example: run Archon bound only to localhost behind a reverse proxy
export HOST=127.0.0.1
export PORT=8080