The driver fails to escape dot and dollar characters in keys used in LINQ queries. An attacker can craft inputs that redirect queries or updates to arbitrary fields, exposing private documents or altering data outside the intended scope. In some cases malformed field names can corrupt documents, making them unreadable until repaired.

MongoDB C# Driver is affected. Applications that accept user‑supplied dictionary keys, field names, or array‑filter identifiers in LINQ queries are vulnerable.

The CVSS score of 7.2 indicates a high‑severity vulnerability. Although EPSS data are not available and the issue is not listed in KEV, the ability to inject characters that redirect queries or cause document corruption provides a substantial attack surface, especially for publicly exposed APIs or services that rely on the C# driver.