CVE-2026-55429
Coder's workspace app upsert allows cross-workspace agent rebinding via user-controlled app ID
Impact
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, `UpsertWorkspaceApp` overwrites an existing app's `agent_id` on a primary-key conflict and `insertAgentApp` accepts the app ID from the provisioner's `CompleteJob` payload without verifying it belongs to the workspace being built. `CompleteJob` runs under `dbauthz.AsProvisionerd` so the authorization layer does not block the cross-workspace upsert. Exploitation requires elevated access as a template author or external provisioner operator. The fix in versions 2.29.7, 2.32.7, 2.33.8, and 2.34.2 verifies that any existing `workspace_apps` row matching the supplied ID belongs to the workspace being built and rejects cross-workspace agent reassignment. No known workarounds are available.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| go | github.com/coder/coder/v2 | >= 2.34.0, < 2.34.2 | 2.34.2 |
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Coder | Coder | before 2.29.17 from 2.30.0 before 2.32.7 from 2.33.0 before 2.33.8 from 2.34.0 before 2.34.2 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/advisories/GHSA-9rjw-3gwp-f59v
- https://github.com/coder/coder/security/advisories/GHSA-9rjw-3gwp-f59v
- https://github.com/coder/coder/pull/26103
- https://github.com/coder/coder/releases/tag/v2.29.17
- https://github.com/coder/coder/releases/tag/v2.32.7
- https://github.com/coder/coder/releases/tag/v2.33.8
- https://github.com/coder/coder/releases/tag/v2.34.2