Coder: Route hijacking through lack of validation of agent-supplied AllowedIPs in tailnet coordinator
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 8.2epss 0.2%
exploitation probability
0.2%top 84% of all CVEs
observed exploitation
nono source reports it
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 tailnet coordinator validates that an agent's `Addresses` derive from its authenticated UUID but applies no equivalent check to `AllowedIPs`. The coordinator forwards agent-supplied `AllowedIPs` verbatim to tunnel peers which install them into the WireGuard peer configuration. The fix in versions 2.29.7, 2.32.7, 2.33.8, and 2.34.2 validates each `AllowedIPs` prefix against the authenticating agent's UUID just like `Addresses`. As a workaround, monitor coordinator logs for agents advertising unexpected `AllowedIPs` prefixes.
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:N
Affected products
coder · coderReferences
https://github.com/coder/coder/pull/26144https://github.com/coder/coder/releases/tag/v2.29.17https://github.com/coder/coder/releases/tag/v2.32.7https://github.com/coder/coder/releases/tag/v2.33.8https://github.com/coder/coder/releases/tag/v2.34.2https://github.com/coder/coder/security/advisories/GHSA-wrq8-fcv5-8hvp