CVE-2026-116575: Mem0: Cross-tenant conversation leak via unescaped delimiter collision in session-scope key (_build_session_scope)

Description

Mem0 provides persistent memory infrastructure for AI agents and applications. Prior to Python SDK 2.0.18 and TypeScript SDK 3.1.6, _build_session_scope() in mem0/memory/main.py and Memory.buildSessionScope() in the TypeScript SDK join caller-controlled user_id, agent_id, and run_id values using unescaped & and = delimiters. A caller can embed another scope component in a controlled identifier so that distinct tenant tuples produce the same session_scope key. Memory.add(), AsyncMemory.add(), and the REST POST /memories flow use that key to read and save recent raw messages, allowing cross-tenant conversation disclosure and eviction or interleaving of another tenant's history. This issue is fixed in Python SDK 2.0.18 and TypeScript SDK 3.1.6.

CVSS vector

CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N

Attack vector

Local

Complexity

High

Privileges

Low

User interaction

None

Confidentiality

High

Integrity

High

Availability

None

Scope

Unchanged

Exploitation

Is it being used?

Exploit prediction (EPSS)0.1% · higher than 1% of CVEs

Exploited in the wildNo evidence yet

CISA KEVNot listed

Ransomware campaign useNot known

Affected products

Which versions

ME

mem0 · mem0ai

< 2.0.18 · source: vendor