CVE-2026-55428 Details
Description
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.
A vulnerability exists in Coder's handling of agent-supplied AllowedIPs in the tailnet coordinator. The coordinator correctly validates that an agent's Addresses are derived from its authenticated UUID but fails to apply the same check to AllowedIPs. As a result, agents can send arbitrary AllowedIPs prefixes, which are forwarded verbatim to tunnel peers and installed into the WireGuard peer configuration. This flaw could be exploited by a malicious workspace agent to intercept and manipulate traffic from other agents.
Upgrade to Coder versions 2.29.17, 2.32.7, 2.33.8, or 2.34.2, all of which include the necessary validation for AllowedIPs. If an immediate upgrade is not possible, monitor coordinator logs for any unexpected AllowedIPs prefixes being advertised by agents.
Metrics
CVSS 4.0 Severity and Vector Strings:
No CVSS 4.0 data is available for this CVE.
CVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
CISA-ADP
Assessed Jul 8, 2026References to Advisories, Solutions, and Tools
By selecting these links, you will be leaving this site. These are references gathered from the official CVE record and are not endorsed by Volerion.
| URL | Source(s) | Tag(s) |
|---|---|---|
| https://github.com/coder/coder/pull/26144 | [email protected] | Issue TrackingPatch |
| https://github.com/coder/coder/releases/tag/v2.29.17 | [email protected] | Release Notes |
| https://github.com/coder/coder/releases/tag/v2.32.7 | [email protected] | Release Notes |
| https://github.com/coder/coder/releases/tag/v2.33.8 | [email protected] | Release Notes |
| https://github.com/coder/coder/releases/tag/v2.34.2 | [email protected] | Release Notes |
| https://github.com/coder/coder/security/advisories/GHSA-wrq8-fcv5-8hvp | [email protected] | PatchVendor Advisory |
Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| CWE-285 | Improper Authorization | [email protected] |
| CWE-863 | Incorrect Authorization | [email protected] |
Affected Products
| Product | Versions |
|---|---|
| coder coder | < 2.29.17 >= 2.30.0, < 2.32.7 >= 2.33.0, < 2.33.8 >= 2.34.0, < 2.34.2 |
CPE
Remediation
| |
Change History
3 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Jul 8, 2026 | Initial Analysis | [email protected] |
| Jul 8, 2026 | CVE Modified | CISA-ADP |
| Jul 8, 2026 | New CVE Received | [email protected] |