CVE-2026-31241: Mem0 Auth Bypass Vulnerability

CVE-2026-31241 Overview

CVE-2026-31241 is a missing authentication vulnerability [CWE-306] in the mem0 1.0.0 memory management server. The flaw resides in the DELETE /memories API endpoint, which accepts requests without verifying caller identity or permissions. An unauthenticated remote attacker can supply arbitrary user_id, run_id, or agent_id query parameters to erase memory records belonging to any user. The result is unauthorized data loss and denial of service against AI agents that depend on the mem0 memory store.

Critical Impact

Unauthenticated remote attackers can permanently delete memory data for any user, agent, or run, disrupting AI applications that rely on mem0 for long-term memory persistence.

Affected Products

• mem0 version 1.0.0 (cpe:2.3:a:mem0:mem0:1.0.0)
• mem0 server deployments exposing the DELETE /memories REST endpoint
• AI agent integrations using mem0 as a backing memory store

Discovery Timeline

• 2026-05-12 - CVE-2026-31241 published to NVD
• 2026-05-14 - Last updated in NVD database

Technical Details for CVE-2026-31241

Vulnerability Analysis

The mem0 server exposes a REST API for storing and retrieving memory records used by AI agents. The DELETE /memories endpoint accepts identifier parameters such as user_id, run_id, and agent_id to scope deletion requests. The endpoint does not enforce authentication or authorization before executing the deletion. Any network-reachable client can issue a DELETE request and remove records associated with any identifier known or guessed by the attacker.

The issue maps to [CWE-306] Missing Authentication for Critical Function. Because the operation is destructive and irreversible, exploitation directly impacts integrity and availability of the memory store. Confidentiality is not affected, since the endpoint deletes rather than returns data. The EPSS probability is 0.127% as of 2026-05-17, reflecting low observed exploitation activity, though the attack requires no skill or tooling beyond a standard HTTP client.

Root Cause

The mem0 1.0.0 server ships without authentication middleware on its memory mutation endpoints. The DELETE /memories handler trusts query parameters supplied by the caller and performs the deletion without verifying that the requester owns or has permission to modify the targeted records. There is no API key check, session validation, or access control list consulted before the database operation executes.

Attack Vector

An attacker reaches any mem0 server exposed on the network and issues an HTTP DELETE request to /memories with a target identifier in the query string. The server processes the request and removes matching memory records. Attackers can enumerate identifiers, target specific tenants, or issue broad deletions to wipe all memory state. No credentials, user interaction, or prior access are required.

The vulnerability is described in prose only because no public proof-of-concept has been published. See the GitHub Project Repository and the Notion CVE Analysis for additional context.

Detection Methods for CVE-2026-31241

Indicators of Compromise

• HTTP DELETE requests to /memories from unexpected source IP addresses or user agents
• Bursts of DELETE /memories requests iterating across multiple user_id, run_id, or agent_id values
• Unexplained absence of memory records reported by downstream AI agent applications
• Access log entries showing successful 200 or 204 responses to DELETE /memories without a preceding authenticated session

Detection Strategies

• Inspect web server, reverse proxy, and API gateway logs for DELETE requests against the /memories path on mem0 hosts
• Correlate deletion events with originating identity context; flag any request lacking an authentication header or session token
• Baseline normal deletion volumes per tenant and alert on deviations that suggest enumeration or mass deletion

Monitoring Recommendations

• Forward mem0 application logs and fronting proxy access logs to a centralized logging or SIEM platform for retention and correlation
• Enable database-level audit logging on the memory store to capture row deletions with timestamps and request context
• Monitor outbound network exposure of mem0 instances to confirm the API is not reachable from untrusted networks

How to Mitigate CVE-2026-31241

Immediate Actions Required

• Remove mem0 1.0.0 servers from untrusted networks and restrict access to known application back-end IP ranges
• Place the mem0 API behind an authenticating reverse proxy or API gateway that enforces token validation on all DELETE requests
• Back up existing memory data so deleted records can be restored if exploitation is detected
• Audit recent access logs for unauthorized DELETE /memories activity and identify any affected tenants

Patch Information

No vendor patch is referenced in the current NVD entry. Monitor the GitHub Project Repository for upstream fixes that add authentication and authorization to the memory mutation endpoints. Track the Notion CVE Analysis for vendor guidance.

Workarounds

• Front the mem0 server with an API gateway that requires an API key or OAuth bearer token on every request
• Apply network-level access control lists so only trusted application services can reach the mem0 listener
• Implement an authorization layer in the calling application that scopes deletion requests to authenticated users and validates ownership of the supplied user_id, run_id, or agent_id
• Disable or block the DELETE /memories route at the proxy layer if deletion is not required by the deployment