CVE-2026-45832: All V1 collection-level endpoints in ChromaDB's Python project pass None for the tenant and database to the authorization layer, allowing attackers to bypass authorization controls by using the V1 endpoints

Synopsis

This is an authorization bypass vulnerability in ChromaDB's Python project. All V1 collection-level API endpoints pass None instead of the actual tenant and database values to the authorization layer, meaning any low-privilege authenticated user can bypass access controls by targeting those endpoints over the network. Successful exploitation gives the attacker read and write access to collection data across tenant and database boundaries, effectively nullifying ChromaDB's multi-tenant isolation. No fix version has been published; HarborGuard tracks this advisory and will make a patched rebuild available as soon as an upstream fix is released.

HarborGuard Coverage

Exploit Conditions

• Network reachabilityRequired

  The attacker must reach the ChromaDB service over the network to send crafted V1 API requests.

• AuthenticationRequired

  A low-privilege account is sufficient; any authenticated user can issue V1 requests and trigger the bypass.

• Victim interactionNot required

  No victim interaction is needed; the attacker sends requests directly to the API without any social engineering step.

• Attack complexityDetail

  Exploitation is reliable under normal conditions, though the AT:P token indicates a specific deployment configuration or timing prerequisite may need to be in place.

Blast Radius

• Reads collection data belonging to other tenants or databases, bypassing the isolation that the authorization layer is intended to enforce.
• Writes to or modifies collection data in tenants and databases the attacker has no legitimate access to, allowing data tampering across organizational boundaries.
• Compromises both the local ChromaDB instance scope and any upstream or downstream systems that depend on ChromaDB's tenant isolation for access decisions.