CVE-2026-81527
MediumCVSS 6.5Exploitation Probability (EPSS)
Low risk8th percentile - higher than 8% of all known CVEs
Summary
A NoSQL/expression injection weakness exists in the LINQ-to-aggregation query translation layer of the MongoDB C# Driver, in both aggregation expression and query filter translation. Special elements in application-supplied values are not properly escaped before the query is sent to the database.
Risk Assessment
A user able to supply values incorporated into an affected query may cause unintended data to be returned or query results to be altered, leading to data exposure or integrity issues.
Recommendation
Upgrade the MongoDB C# Driver to a patched version. Avoid directly embedding user input into queries; use parameterized queries and input validation.
Original NVD description (English source)
A NoSQL/expression injection weakness exists in the LINQ-to-aggregation query translation layer of the MongoDB C# Driver, in both aggregation expression and query filter translation. When application-supplied values are embedded in certain query constructs, special elements contained within those values are not properly escaped before the resulting query is transmitted to the database, so portions of the value may be interpreted by the database as query logic rather than as data. A user able to supply values that an application incorporates into an affected query may thereby cause unintended data to be returned or query results to be altered.