n8n versions before 1.123.80, from 2.0.0 before 2.39.6, and from 2.40.0 before 2.40.1 contain a NoSQL injection vulnerability in the MongoDB Chat Memory node that fails to validate the sessionId parameter. Unauthenticated attackers can supply MongoDB query operators in the sessionId field to access conversation histories from other users and perform unauthorized write and delete operations.
Weakness
The product generates a query intended to access or manipulate data in a data store such as a database, but it does not neutralize or incorrectly neutralizes special elements that can modify the intended logic of the query.
Extended Description
Depending on the capabilities of the query language, an attacker could inject additional logic into the query to:
The ability to execute additional commands or change which entities are returned has obvious risks. But when the product logic depends on the order or number of entities, this can also lead to vulnerabilities. For example, if the query expects to return only one entity that specifies an administrative user, but an attacker can change which entities are returned, this could cause the logic to return information for a regular user and incorrectly assume that the user has administrative privileges. While this weakness is most commonly associated with SQL injection, there are many other query languages that are also subject to injection attacks, including HTSQL, LDAP, DQL, XQuery, Xpath, and “NoSQL” languages.