EUVD-2026-333836

fkie_cve-2026-55432

Coder allows organizations to provision remote development environments via Terraform. Prior to versions 2.29.7, 2.32.7, 2.33.8, and 2.34.2, the `CreateSubAgent` RPC did not validate a requested app sharing level against the template's `MaxPortSharingLevel` before persisting workspace apps, letting a workspace owner exceed the administrator's configured maximum. Exploitation requires the ability to register sub-agent apps in a workspace the attacker controls. The fix in versions 2.29.7, 2.32.7, 2.33.8, and 2.34.2clamps the sub-agent app sharing level to the template's `MaxPortSharingLevel`. As a workaround, disable wildcard app hostnames (`CODER_WILDCARD_ACCESS_URL`) to block subdomain-based app routing.

GHSA-x9qq-2qh5-8rxf — Coder's sub-agent app registration bypasses template port-sharing policy enforcement

Affected: Go: github.com/coder/coder/v2

### Summary

The `CreateSubAgent` RPC did not validate a requested app sharing level against the template's `MaxPortSharingLevel` before persisting workspace apps, letting a workspace owner exceed the administrator's configured maximum.

> **Note:** Exploitation requires the ability to register sub-agent apps in a workspace the attacker controls.

### Impact

A workspace owner with an agent token could register a sub-agent app as `PUBLIC` even when the template's `MaxPortSharingLevel` was `owner`, exposing the app to unauthenticated users via the wildcard app domain. This affected only deployments using Enterprise port-sharing policy and wildcard app hostnames and required an authenticated workspace owner with an agent token.

### Patches

The fix clamps the sub-agent app sharing level to the template's `MaxPortSharingLevel`.

The fix was backported to all supported release lines:

| Release line | Patched version | |---|---| | 2.34 | [v2.34.2](https://github.com/coder/coder/releases/tag/v2.34.2) | | 2.33 | [v2.33.8](https://github.com/coder/coder/releases/tag/v2.33.8) | | 2.32 | [v2.32.7](https://github.com/coder/coder/releases/tag/v2.32.7) | | 2.29 (ESR) | [v2.29.17](https://github.com/coder/coder/releases/tag/v2.29.17) |

### Workarounds

Disable wildcard app hostnames (`CODER_WILDCARD_ACCESS_URL`) to block subdomain-based app routing.

### Resources

- Fix: #26061

### Credits

Coder would like to thank Anthropic's Security Team (ANT-2026-22452) for independently disclos…

Most recent entries from all

EUVD-2026-333836

fkie_cve-2026-55432

GHSA-x9qq-2qh5-8rxf — Coder's sub-agent app registration bypasses template port-sharing policy enforcement