CVE-2026-49948 describes a missing authorization vulnerability in mem0 (versions <=0.2.8) where the POST /configure endpoint allows modification of global LLM provider and embedder settings. The endpoint authenticates users via JWT or X-API-Key but does not validate the caller's role or permissions, enabling any authenticated user with an API key to redirect traffic to an attacker-controlled server. The malicious configuration is persisted in the backend PostgreSQL database and survives server restarts, impacting all users and API keys on the affected instance. The vulnerability was fixed in commit ae7f406.

An attacker with any valid distributed API key can modify global configuration to redirect LLM and embedder traffic to a malicious server. This compromises the integrity and confidentiality of all LLM-related data and operations on the affected mem0 instance. The persistence of the malicious configuration in PostgreSQL means the compromise survives server restarts and affects all users and API keys on the instance, potentially leading to widespread data interception or manipulation.

A fix for this vulnerability exists and was introduced in commit ae7f406. Users should upgrade mem0 to a version later than 0.2.8 that includes this fix. Until upgraded, restrict API key distribution and monitor for unauthorized configuration changes. Patch status is not explicitly confirmed in the advisory, so verify the vendor's repository or advisory for the exact patched version and apply the official fix.