The $internalIndexKey aggregation expression can be used by any authenticated user to crash a MongoDB server (mongod). The expression fails to handle compound wildcard index specifications, triggering an internal consistency check that aborts the server process. The user must be able to run an aggregation pipeline.

Using expressions that generate large arrays it is possible to craft a query that creates very large intermediate objects in memory, causing the server to crash with OOM error.

An issue in the server’s Atlas Search integration allows an authenticated user to bypass per-user access controls.

In sharded topologies, the $search and $searchMeta aggregation stages use internal routing that is normally populated only by the trusted router during sharded search planning. Due to insufficient input validation, an authenticated client can supply these fields directly.

An authenticated user with basic write privileges can cause the mongod process to terminate abnormally by sending a crafted transaction command with an incomplete set of required fields. The issue stems from inconsistent validation across related transaction command parameters, resulting in a fatal internal invariant failure and denial of service.

An authenticated user with low privileges may be able to perform unauthorized reads and writes on data protected by role-based query-level access controls, due to insufficient validation of certain client-supplied command parameters. The issue affects find, update, delete, and aggregate commands in non-apiStrict configurations.

During query planning when reading the sort pattern in raw BSONObj form, in some places we don’t explicitly handle the meta expression case. This may lead to incorrect transformations leading to invariant failure.

An authenticated user with limited read privileges may be able to access documents from collections they are not authorized to read, due to an inconsistency in how the $graphLookup aggregation stage is evaluated during authorization and during execution. Affected scenarios involve collections referenced within existing view pipeline definitions.

An authenticated user may be able to view session metadata belonging to other users on the system through the $listSessions aggregation stage. This information is normally restricted to users with cluster-level administrative privileges, and includes active session identifiers, associated usernames, and activity timestamps.

An authenticated user with write privileges on a Queryable Encryption-enabled collection may be able to modify internal encryption metadata fields that are intended to be server-controlled, by sending crafted write commands through the mongos router on a sharded cluster. This can result in corruption of encrypted query correctness.

An authenticated user with standard read/write privileges can cause the mongod process to terminate due to an out-of-memory condition by sending a crafted aggregation command. MongoDB's libmongocrypt library insufficiently validates payload-supplied values, which can result in an excessively large memory allocation.

Certain query operations involving deeply nested $jsonSchema constructs can trigger disproportionate CPU consumption in affected MongoDB deployments, potentially leading to resource exhaustion. The resulting CPU-bound operation cannot be interrupted through standard administrative controls.

A user with read-only privileges is able to craft an aggregation pipeline using the $linearFill window function operator with a specific sortBy expression type to cause the mongod process to terminate abnormally, resulting in denial of service. The issue stems from insufficient validation of sort specifications during execution.

Improper handling of DBPointer objects during BSON serialization in MongoDB's server-side JavaScript engine can result in internal process memory contents being included in data returned to the client. This constitutes an unintended information disclosure affecting deployments that use server-side JavaScript.

When PROXY protocol v2 is used on the Unix domain socket path, roles derived from X.509 client certificates may not be validated against the configured tlsCATrusts allow-list. This can result in unintended role assignments following MONGODB-X509 authentication. Affected scenarios require local access to the proxy Unix domain socket and a valid X.509 certificate issued by a trusted certificate authority.

An authenticated user holding cursor termination privileges on one database may incorrectly be permitted to terminate active cursors on a separate database, disrupting ongoing query operations for other users. The behavior stems from an authorization check that does not correctly scope privileges to the appropriate namespace.

An authenticated user can cause excessive CPU consumption or out-of-memory conditions on a MongoDB server by sending a crafted Queryable Encryption find payload containing an unvalidated field used to control an internal computation loop. The resulting resource exhaustion degrades availability for other operations.

A MongoDB server initiating an outbound TLS connection may terminate abnormally when processing a malformed OCSP response from a remote peer during the TLS handshake. OCSP stapling validation is enabled by default for outgoing TLS connections. Affected scenarios require the remote peer to hold a certificate issued by the cluster's trusted certificate authority, or for the connection to traverse an untrusted network path.

An authenticated user with read access can cause the mongod process to be terminated through certain aggregation expressions that execute server-side JavaScript. The issue involves improper memory handling during document processing.

When compute mode is enabled on a standalone mongod instance, insufficient validation of externally sourced BSON data during aggregation pipeline processing can result in memory corruption, potentially leading to process termination or other unintended behavior. This configuration is non-default and requires explicit enablement at startup.

An authenticated user with read-only privileges can cause the mongod process to terminate abnormally by issuing a crafted aggregation command, resulting in denial of service for all connected clients until the process is restarted. The issue stems from an internal engine selection inconsistency triggered by a specific combination of aggregation options.

An unauthenticated remote client can cause excessive CPU consumption on a MongoDB server by sending a specific combination of parameters to the awaitable hello command in exhaust mode. The server's handling of this combination results in a response loop that bypasses normal throttling, allowing a small number of connections to degrade server availability.

An authenticated user can cause the mongod process to be terminated by the operating system under memory pressure via the $rankFusion and $scoreFusion aggregation stages. The issue originates in the server's error-handling path and requires the ability to run aggregation queries.

An authenticated user can cause a {{mongod}} process to be terminated by the operating system under memory pressure by performing a specific data type conversion operation within MongoDB's aggregation framework. The behavior stems from disproportionate memory consumption during this operation, and requires both write access to the database and the ability to run aggregation queries.

A missing bounds check in the BSON CodeWScope element accessors allows an attacker to trigger an out-of-bounds heap read via a crafted aggregation pipeline. The vulnerability can be exploited by an authenticated user by generating a malformed BSONColumn data containing a CodeWScope element, bypassing wire-level BSON validation. When the forged element is decompressed, the unchecked size value is used in pointer arithmetic, causing either a server crash or disclosure of adjacent heap memory contents.

A vulnerability was discovered in MongoDB Server where the server-side MozJS scripting engine unconditionally registered a module loading hook that enables JavaScript calls to read arbitrary files from the host filesystem using the mongod process's privileges. An authenticated user could exploit this through crafted aggregation pipeline commands to read sensitive files accessible to the MongoDB server process.

A use-after-free vulnerability exists in MongoDB Server's server-side JavaScript engine when converting BSON documents to JavaScript arrays. An authenticated user with read privileges who is able to run server-side JavaScript (for example, via $where or $function) can cause the server to access memory that has already been freed. This may result in disclosure of information from the mongod process memory or a denial of service through a server crash.

A vulnerability in MongoDB Server's BSON validation logic allows an unauthenticated user to crash the mongod process by sending a specially crafted message. The BSON validator's handling of certain nested binary data structures permits uncontrolled mutual recursion between validation functions, where each re-entry resets internal depth tracking.

MongoDB server may log authentication parameters, including credentials, to the server log during SASL authentication. When connection health metric logging is enabled, the full authentication parameters are written to the log without redaction.

An authenticated user with the read role may read limited amounts of uninitialized stack memory via specially-crafted issuances of the filemd5 command

The $internalApplyOplogUpdate aggregation pipeline stage can be used to execute a document diff containing a malformed binary diff to return memory out-of-bounds or crash the server. $internalApplyOplogUpdate can be executed by any authenticated user with access to the aggregate command.