CVE-2026-55436: Coder's AI Bridge Proxy skips TLS certificate verification in default configuration

Severity: high (CVSS 7.4 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-07-08 · updated 2026-07-08
Weakness: CWE-295

Description

Coder allows organizations to provision remote development environments via Terraform. Starting in version 2.30.0 and prior to versions 2.32.7, 2.33.8, and 2.34.2, the AI Bridge Proxy (`aibridgeproxyd`) created a goproxy server whose default transport set `InsecureSkipVerify: true` and only assigned a secure transport when an upstream proxy was configured. In the default configuration (no upstream proxy), outbound HTTPS to the Coder access URL accepted any TLS certificate. Practical exploitation requires an on-path (man-in-the-middle) position between the AI Bridge Proxy and the Coder server. Deployments where they are co-located over loopback are effectively unaffected. The fix in versions 2.32.7, 2.33.8, and 2.34.2 applies the secure transport (TLS 1.2 or higher using system root CAs) unconditionally. As a workaround, ensure the Coder access URL uses a trusted certificate and secure the network path between the AI Bridge Proxy and the Coder server (for example, loopback or mTLS).

Affected products

coder: from 2.30.0 before 2.32.7; from 2.33.0 before 2.33.8; from 2.34.0 before 2.34.2 — fixed in 2.32.7, 2.33.8, 2.34.2

How to fix

Upgrade to a fixed version: coder 2.32.7, 2.33.8, 2.34.2. Check the vendor advisory for mitigations.

References

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