Mem0 Cross-Tenant Conversation Leak via Delimiter Collision

A vulnerability in Mem0's session-scope key construction allows attackers who control a run_id or agent_id to craft values containing delimiters that collide with other tenants' scope strings, enabling unauthorized access to and corruption of conversation history across tenant boundaries.

Disclosed 28 October 2026 · Record updated 28 October 2026

Impact

Cross-tenant confidentiality breach allowing unauthorized access to conversation content including potentially sensitive data, and cross-tenant data corruption through message eviction and interleaving.

Our coverage

A masked figure inserts a counterfeit key into a filing cabinet, opening drawers meant for others, scattering private letters across a dark office floor.

Vulnerabilities

Mem0 memory keys can be forged to read other tenants' chats

A GitHub advisory published on 28 October 2026 says attackers who control a single identifier can collide with another tenant's conversation history in Mem0.

28 Oct 2026

Sources

github.comhttps://github.com/advisories/GHSA-5324-3w58-qpp2