Advisories for Golang/Github.com/Coder/Coder package

2026

Coder: Unauthenticated SSRF via Azure Instance Identity Endpoint

Unauthenticated semi-blind Server-Side Request Forgery (SSRF) via the Azure instance identity endpoint (POST /api/v2/workspaceagents/azure-instance-identity). An external attacker can force the Coder server to issue HTTP GET requests to arbitrary internal or external hosts by submitting a crafted PKCS#7 signature. The server does not return the target's response body, but error messages in the API response reveal whether the target is reachable and what type of failure occurred.

Coder: Unauthenticated SSRF via Azure Instance Identity Endpoint

Unauthenticated semi-blind Server-Side Request Forgery (SSRF) via the Azure instance identity endpoint (POST /api/v2/workspaceagents/azure-instance-identity). An external attacker can force the Coder server to issue HTTP GET requests to arbitrary internal or external hosts by submitting a crafted PKCS#7 signature. The server does not return the target's response body, but error messages in the API response reveal whether the target is reachable and what type of failure occurred.

Coder: PKCS#7 signature bypass in Azure instance identity allows unauthenticated agent token theft

azureidentity.Validate() verifies that the PKCS#7 signer certificate chains to a trusted Azure CA but never verifies the PKCS#7 signature itself. An attacker can embed a legitimate Azure certificate alongside arbitrary content e.g. {"vmId":"<target>"} and the forged vmId will be accepted returning the victim workspace agent's session token. No authentication is required. The attacker only needs to know a target VM's vmId which is a UUIDv4. that's a practical limitation which …

Coder: PKCS#7 signature bypass in Azure instance identity allows unauthenticated agent token theft

azureidentity.Validate() verifies that the PKCS#7 signer certificate chains to a trusted Azure CA but never verifies the PKCS#7 signature itself. An attacker can embed a legitimate Azure certificate alongside arbitrary content e.g. {"vmId":"<target>"} and the forged vmId will be accepted returning the victim workspace agent's session token. No authentication is required. The attacker only needs to know a target VM's vmId which is a UUIDv4. that's a practical limitation which …

2025
2024

Coder's OIDC authentication allows email with partially matching domain to register

Summary A vulnerability in Coder's OIDC authentication could allow an attacker to bypass the CODER_OIDC_EMAIL_DOMAIN verification and create an account with an email not in the allowlist. Deployments are only affected if the OIDC provider allows users to create accounts on the provider (such as public providers like google.com). Details During OIDC registration, the user's email was improperly validated against the allowed CODER_OIDC_EMAIL_DOMAINs. This could allow a user with a …

Coder's OIDC authentication allows email with partially matching domain to register

Summary A vulnerability in Coder's OIDC authentication could allow an attacker to bypass the CODER_OIDC_EMAIL_DOMAIN verification and create an account with an email not in the allowlist. Deployments are only affected if the OIDC provider allows users to create accounts on the provider (such as public providers like google.com). Details During OIDC registration, the user's email was improperly validated against the allowed CODER_OIDC_EMAIL_DOMAINs. This could allow a user with a …