A security issue was discovered in MongoDB mongos (the sharded cluster router) where an authenticated user with readWrite privileges could crash the mongos process by crafting a specially formed aggregation pipeline. The issue leverages an internal aggregation stage that lacks proper authorization checks despite being intended for internal use, allowing a subsequent stage to be forced to execute on the router under conditions it was not designed to handle. This results in an unhandled fatal error that causes the mongos process to immediately abort, resulting in denial of service for all clients routed through the affected mongos instance.

MongoDB Server's collection validation feature may not properly handle certain expressions stored in a validator. In some cases, this can cause the server process to stop running when a document is later inserted. The behavior can occur for authenticated users with write access.

An issue in MongoDB Server's aggregation framework can cause certain constant values to be handled incorrectly during internal query rewriting. Under certain conditions, an authenticated user with read access may receive field values in aggregation output that the query did not intend to return.

A security issue was discovered in MongoDB mongos (the sharded cluster router) where an authenticated user with readWrite privileges could crash the mongos process by crafting a specially formed aggregation pipeline. The issue leverages an internal aggregation stage that lacks proper authorization checks despite being intended for internal use, allowing a subsequent stage to be forced to execute on the router under conditions it was not designed to handle. This results in an unhandled fatal error that causes the mongos process to immediately abort, resulting in denial of service for all clients routed through the affected mongos instance.

Use of freed memory in the aggregation feature of MongoDB Server can cause the server to read data from a memory area after it has been released. When an internal aggregation stage is combined with a batch size of 0, the server may read from memory that is no longer in use. Because that memory can be reused for other data before it is read, query results returned to the client may contain unrelated data from the server process. Depending on the state of memory at the time, the server process may also terminate unexpectedly. The behavior can occur when an authenticated user with read privileges runs an aggregate command that combines these two settings.

An authenticated Ops Manager organization member can retrieve another member's pending authenticator enrollment seed through user-listing endpoints while that member's enrollment is unconfirmed. This results in disclosure of secret authentication material to another member of the same organization or project.

An authenticated Ops Manager user with a read-only project role can retrieve a daily host monitoring record associated with a different project when they possess the required record identifier. Insufficient ownership validation can expose deployment metadata, including host and configuration details.

An unauthenticated user with network access to the Ops Manager web port can repeatedly request monitoring endpoints that perform costly work without rate limiting. This can temporarily slow other traffic served by the same process while requests continue.

The MongoDB Python Driver's binary accelerator can read outside a buffer when an application decodes malformed BSON containing a truncated regular-expression element without a trailing NUL byte. An actor who can supply BSON to the documented decode or decodeall API can cause the application process to terminate when the C extension is loaded. The driver's normal database wire-protocol path does not reach this code.

The BSON encoder in the MongoDB PHP Driver does not check some return values after a document exceeds libbson's size limit. This can leave the encoder in an invalid state. An unauthenticated actor who can cause an affected application to encode an unusually large data structure can terminate the PHP worker or cause the resulting document to omit fields. No MongoDB server connection or database authentication is required.

The BSON encoder in the MongoDB PHP Driver converts a string length to a 32-bit value without validation. When an affected application encodes a string near 4 GiB, the allocation size can wrap while the copy operation uses the original length. The resulting heap buffer overflow can corrupt process memory or terminate the PHP process. Reaching this issue requires a non-default runtime configuration that permits multi-gigabyte values. No MongoDB server interaction is required.

Application denial of service via missing BSON array length validation in MongoDB Go Driver

An integer overflow in BSON value-length handling in the MongoDB Go Driver can cause a runtime panic when an application validates or accesses a malformed BSON document. An unauthenticated actor who can supply BSON bytes to an affected application may terminate an unprotected application process, causing a denial of service. The driver's server-monitoring path contains panic recovery and is limited to server-selection failure.

The explicit decryption component of MongoDB libmongocrypt can return an unrecognized encrypted payload unchanged instead of returning a decryption error. An actor who can modify stored encrypted fields, such as a database writer, server, or network intermediary, can cause an affected application to process the supplied bytes as decrypted plaintext.

Improper state management in MongoDB libmongocrypt can cause provider-specific data to be treated as an incompatible type when cleaning up a key document containing duplicate masterKey fields. An authenticated actor who can modify key vault documents, or a server that returns such a key document, can cause invalid memory access and invalid frees in the client process. This can terminate the application or corrupt process memory.

An integer underflow in the KMS endpoint-parsing logic of MongoDB libmongocrypt can cause an allocation failure that terminates the application process. This can occur when an authenticated user modifies a key document in the key vault collection, or when an application accepts a KMS endpoint containing a colon after its path or query during key creation. The issue does not access memory outside its allocated bounds.

The MongoDB C++ Driver discards content after an embedded NUL byte in certain field and collection names accepted by the collection API. This can cause the driver and the calling application to interpret the same name differently. An authenticated actor who can influence a name passed by an affected application can cause the application to read distinct values from an unintended field or rename an unintended collection. These operations use the application's existing database credentials.

An incorrect calculation in Decimal128 string parsing in the MongoDB C Driver can accept certain over-precision inputs containing leading zeros instead of rejecting them. This produces a value different from the supplied text. An actor who can provide a decimal string to an embedding application, including through Extended JSON parsing, can cause the application to store or use an incorrect numeric value.

The BSON buffer-reservation API in the MongoDB C Driver can record a length smaller than the five-byte BSON minimum. Later append or comparison operations can underflow unsigned length calculations and read or write outside the document buffer. An actor who can influence the length supplied by an embedding application can cause the application to terminate or read or corrupt adjacent process memory. Reaching this issue requires the application to pass an undersized value to bsonreservebuffer and then perform an affected operation.

An off-by-one error in the BSON bulk document writer in the MongoDB C Driver can write one zero byte immediately past a heap allocation when a document ends at a specific buffer boundary. An actor who can influence the size of documents serialized by an embedding application can corrupt adjacent process memory or terminate the process. Reaching this issue requires the application to use the BSON bulk-writer API and produce a precise cumulative document size.

An out-of-bounds read in SCRAM authentication response parsing in the MongoDB C Driver can read one byte beyond a fixed-size buffer when processing a malformed server-final message. A server or network intermediary able to provide this message before server-signature verification can cause the application using the driver to terminate. The extra byte is not returned through the protocol.

In MongoDB Controllers for Kubernetes, insufficient validation of Ops Manager backup configuration may allow a user who can modify an OpsManager custom resource to cause unintended administrative changes in Ops Manager. This affects deployments using Enterprise Ops Manager backup reconciliation.

Deserialization of untrusted data in the command monitoring support of the MongoDB PHP Driver can cause class names embedded in document content to be honored when the driver builds monitoring event objects. When an application registers a command monitoring subscriber and includes untrusted data in a database operation, an unauthenticated party who controls that data may cause an application class implementing the driver's persistable interface to be instantiated and its unserialization method invoked with the supplied data. The resulting impact depends on the classes available in the application.

An out-of-bounds write in the connection-monitoring logic of the MongoDB C Driver may allow an unauthenticated party who controls name resolution and the responses of the hosts named in a client's connection string to write beyond the end of a heap buffer. This may cause the application using the driver to terminate unexpectedly.

MongoDB Compass can interpolate a database name without escaping into the initial input of its embedded MongoDB shell when a user opens the shell from that database's view. A user with privileges to create databases on a server that a Compass user connects to may, under specific conditions, have content evaluated as shell input within the Compass process, with that process's privileges. This requires the Compass user to open the shell for the affected database.

Mongoid does not neutralize a string-typed query criterion supplied to its query builder, and instead passes it to the database as a server-side JavaScript expression. An unauthenticated party able to influence the value an application supplies as a query argument may cause code of their choosing to be evaluated by the database engine. This may result in unintended disclosure of stored field values, unintended selection of documents for application-initiated writes, and reduced database performance.

Mongoid does not restrict which query operators may come from caller-supplied filter data when an application hands that data to its query-building methods. In an application that forwards externally supplied filter parameters in this way, a party with no credentials may influence how the database evaluates the query. This may result in unintended disclosure of stored field values and in reduced database performance.

An inefficient regular expression complexity issue in the in-memory query evaluation component of the Mongoid library may allow an unauthenticated party to cause excessive processing within an embedding application process. Applications that place user-supplied text into a pattern-matching query condition on an embedded association may become unresponsive.

Mongoid contains an unsafe reflection weakness in the query path used for embedded documents. An application that passes an externally supplied field name to certain in-memory query methods may allow an unauthenticated party to obtain unintended disclosure of stored document data and to permanently remove stored records.

A protection mechanism failure in the object-document mapper's encryption configuration generation can cause fields that an application declared for client-side field-level encryption to be written and kept in cleartext, without any error or warning. A party holding ordinary read access to the database can then read values that were intended to be protected from that party. This may result in unintended disclosure of sensitive information.