vulnerability / NVI-00017594 / Revision 1
Coder's workspace agent API insecure redirect handling allowed cross-agent file read and write
GitHub lists this reviewed advisory for github.com/coder/coder/v2, github.com/coder/coder/v2, github.com/coder/coder/v2, github.com/coder/coder/v2. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.
This report has not inspected your inventory, configuration, deployed build, reachability or evidence. A catalog listing and a severity score do not establish exposure or compromise.
01 / Meaning
Why it matters
Published affected context helps an owner decide what evidence to gather. This report has not examined your application.
8.3 high
GitHub source severity; exploitability and local consequence require separate evidence.
As of · GitHub Advisory Database
02 / Applicability
The affected context
Affected versions, configuration prerequisites and known exclusions are public. Confirm each one against the deployed service.
github.com/coder/coder/v2
source listed>= 2.34.0, < 2.34.4
### Summary `agentConn.apiClient()` used the default redirect behavior of `http.Client` while its custom transport dialed the host from the request URL as long as the port was the workspace agent HTTP API port (`4`). Agent tailnet IPs are deterministic from agent UUIDs, so a malicious workspace agent could return a redirect to another agent's tailnet IP and cause the control-plane client to send the follow-up workspace agent API request to the victim agent instead of the intended agent. Redirects that preserve the method and body, such as HTTP 307 and 308, allow replay of write and process-start requests. HTTP 301, 302 and 303 redirects only convert POST requests to GET requests, so they are sufficient to demonstrate redirected reads but not write or command-execution primitives. ### Impact An authenticated user with a running workspace and control of a modified workspace agent can redirect workspace agent API requests made to their agent toward another online workspace agent reachable on the tailnet. If the attacker knows the victim agent UUID, they can derive the victim's tailnet IP and target the victim's file APIs to read or write files as the victim workspace user. In aff
github.com/coder/coder/v2
source listed>= 2.33.0, < 2.33.10
### Summary `agentConn.apiClient()` used the default redirect behavior of `http.Client` while its custom transport dialed the host from the request URL as long as the port was the workspace agent HTTP API port (`4`). Agent tailnet IPs are deterministic from agent UUIDs, so a malicious workspace agent could return a redirect to another agent's tailnet IP and cause the control-plane client to send the follow-up workspace agent API request to the victim agent instead of the intended agent. Redirects that preserve the method and body, such as HTTP 307 and 308, allow replay of write and process-start requests. HTTP 301, 302 and 303 redirects only convert POST requests to GET requests, so they are sufficient to demonstrate redirected reads but not write or command-execution primitives. ### Impact An authenticated user with a running workspace and control of a modified workspace agent can redirect workspace agent API requests made to their agent toward another online workspace agent reachable on the tailnet. If the attacker knows the victim agent UUID, they can derive the victim's tailnet IP and target the victim's file APIs to read or write files as the victim workspace user. In aff
github.com/coder/coder/v2
source listed>= 2.30.0, < 2.32.9
### Summary `agentConn.apiClient()` used the default redirect behavior of `http.Client` while its custom transport dialed the host from the request URL as long as the port was the workspace agent HTTP API port (`4`). Agent tailnet IPs are deterministic from agent UUIDs, so a malicious workspace agent could return a redirect to another agent's tailnet IP and cause the control-plane client to send the follow-up workspace agent API request to the victim agent instead of the intended agent. Redirects that preserve the method and body, such as HTTP 307 and 308, allow replay of write and process-start requests. HTTP 301, 302 and 303 redirects only convert POST requests to GET requests, so they are sufficient to demonstrate redirected reads but not write or command-execution primitives. ### Impact An authenticated user with a running workspace and control of a modified workspace agent can redirect workspace agent API requests made to their agent toward another online workspace agent reachable on the tailnet. If the attacker knows the victim agent UUID, they can derive the victim's tailnet IP and target the victim's file APIs to read or write files as the victim workspace user. In aff
github.com/coder/coder/v2
source listed>= 2.27.0, < 2.29.19
### Summary `agentConn.apiClient()` used the default redirect behavior of `http.Client` while its custom transport dialed the host from the request URL as long as the port was the workspace agent HTTP API port (`4`). Agent tailnet IPs are deterministic from agent UUIDs, so a malicious workspace agent could return a redirect to another agent's tailnet IP and cause the control-plane client to send the follow-up workspace agent API request to the victim agent instead of the intended agent. Redirects that preserve the method and body, such as HTTP 307 and 308, allow replay of write and process-start requests. HTTP 301, 302 and 303 redirects only convert POST requests to GET requests, so they are sufficient to demonstrate redirected reads but not write or command-execution primitives. ### Impact An authenticated user with a running workspace and control of a modified workspace agent can redirect workspace agent API requests made to their agent toward another online workspace agent reachable on the tailnet. If the attacker knows the victim agent UUID, they can derive the victim's tailnet IP and target the victim's file APIs to read or write files as the victim workspace user. In aff
03 / Response
What to do next
- investigate
Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.
Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. GitHub Advisory Database
A fixed release is not deployment evidence.
Check current vendor support and compatibility. After making a change, verify the deployed build and relevant runtime conditions. Keep the evidence, owner and time. An updated lockfile alone does not prove what is running.
04 / Limits
What this report cannot establish
- Customer inventory, deployment, reachability and exploitation have not been inspected.
05 / Provenance
Sources you can inspect
Each assertion retains its source. Mirrored records may repeat one underlying publisher; additional links are not independent corroboration.
- GHSA-qrwj-vh9x-gw5v ↗
GitHub Advisory Database · vendor advisory
Observed . GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.
Public revision history
Only published revisions appear here. Routine fetches do not create a material-change event.
- Revision 1 ·
First indexed by Null; source disclosure date is shown separately.