Horizon Alert
Summary of the vulnerability and why it matters
A vulnerability has been identified in the Coder platform, which is used for provisioning remote development environments. This issue could allow an attacker to embed malicious content within a legitimate certificate, potentially leading to unauthorized access to session tokens. The primary concern is to confirm if our organization utilizes this specific technology and is exposed.
- Unchecked certificate signatures could expose sensitive tokens.
- Understand exposure; confirm relevance for Coder environments.
- Prioritize assessing Coder's use and potential impact.
Attack Path
How an attacker could exploit the issue
An attacker could target a remote development environment provisioned by Coder. By crafting a malicious PKCS#7 signature with a legitimate Azure certificate and a fabricated virtual machine ID, an attacker could trick the `azureidentity.Validate()` function. This vulnerability, which does not require authentication, could then lead to the exposure of a victim workspace agent's session token.
- Attacker needs target VM ID.
- Signature validation bypass.
- Session token theft risk.
Live Threat
Current exploitation, exposure, and threat context
This vulnerability could allow an attacker to embed malicious content within a PKCS#7 certificate, tricking the system into accepting a forged VM ID. If successful, the attacker could obtain the victim workspace agent's session token without authentication, provided they know the target VM's UUIDv4.
- Session tokens could be exposed.
- Unauthenticated embedding of malicious content.
- Unauthorized access to workspace agent.
Operational Fix
Recommended remediation, mitigation, and detection steps
The platform and infrastructure teams are likely responsible for managing Coder and its Terraform configurations. The initial focus should be on identifying all instances of Coder, determining their reachability and criticality, and then verifying the accountable owner for remediation or applying the vendor-provided workaround.
- Platform/Infrastructure teams own the issue.
- Verify Coder instances and their exposure.
- Plan remediation or apply workaround.
