CVE-2026-36719: An information disclosure vulnerability in the /api/v1/user/info endpoint of AgentChat v2

Synopsis

An information disclosure vulnerability in the /api/v1/user/info endpoint of AgentChat v2.3.0 allows any unauthenticated attacker to enumerate user IDs over the network and retrieve sensitive account data. No credentials or user interaction are required to exploit this flaw. Successful exploitation exposes SHA256 password hashes for all enumerable user accounts, which can then be targeted in offline cracking attacks. HarborGuard is tracking this advisory and will make a patched-image rebuild available as soon as an upstream fix is published.

HarborGuard Coverage

Exploit Conditions

• Network reachabilityRequired

  The vulnerable endpoint is exposed over the network, so an attacker must be able to reach the service via HTTP/HTTPS to exploit it.

• AuthenticationNot required

  No credentials of any kind are needed; the /api/v1/user/info endpoint accepts unauthenticated requests.

• Victim interactionNot required

  Exploitation is fully automated and requires no action from any user or administrator of the affected system.

• Attack complexityDetail

  Attack complexity is low, meaning the exploit is reliable and requires no special conditions, race timing, or environmental configuration.

Blast Radius

• An attacker reads SHA256 password hashes for any user account whose ID can be enumerated, enabling offline cracking attempts against those hashes.
• Full user ID enumeration exposes the scope of all registered accounts, leaking information about the user base size and potentially usernames or profile data returned by the endpoint.
• Cracked credentials derived from the exposed hashes can be used to authenticate to AgentChat or to other services where users reuse passwords.