CVE-2026-4359 is a low-severity vulnerability in the MongoDB C Driver caused by improper neutralization of null byte characters (CWE-158). An attacker, such as a compromised third-party cloud server or a man-in-the-middle, can send a malformed HTTP response containing null bytes that triggers a crash in applications using this driver. Exploitation requires high privileges and user interaction, and the attack complexity is high. There are no known exploits in the wild, and no patches have been released yet. The vulnerability primarily impacts the availability of applications relying on the MongoDB C Driver by causing crashes, but it does not affect confidentiality or integrity. Organizations using this driver in their infrastructure should monitor for updates from MongoDB Inc and consider network-level protections to mitigate man-in-the-middle risks. Countries with significant MongoDB usage and cloud infrastructure reliance are more likely to be affected. Overall, the threat is limited in scope and impact but should be addressed to maintain service stability.
CVE-2026-4148 is a high-severity use-after-free vulnerability in MongoDB Server versions 7.0, 8.0, and 8.2. It can be exploited by an authenticated user with read role privileges in sharded clusters by issuing a specially crafted $lookup or $graphLookup aggregation pipeline. This vulnerability does not require user interaction or elevated privileges beyond read access but can lead to high impact on confidentiality, integrity, and availability. No known exploits are currently reported in the wild. The vulnerability stems from improper memory management (CWE-416) during aggregation operations in sharded environments. Organizations using affected MongoDB versions in sharded configurations should prioritize patching or mitigating this issue to prevent potential exploitation. The CVSS 4.
An authenticated user with the read role may read limited amounts of uninitialized stack memory via specially-crafted issuances of the filemd5 command.
The mongo-go-driver repository contains CGo bindings for GSSAPI (Kerberos) authentication on Linux and macOS. The C wrapper implementation contains a heap out-of-bounds read vulnerability due to incorrect assumptions about string termination in the GSSAPI standard. Since GSSAPI buffers are not guaranteed to be null-terminated or have extra padding, this results in reading one byte past the allocated heap buffer.
Under specific conditions when processing a maliciously crafted value of type Hash r, Mongoid::Criteria.from_hash may allow for executing arbitrary Ruby code.
MongoDB Server may experience an out-of-memory failure while evaluating expressions that produce deeply nested documents. The issue arises in recursive functions because the server does not periodically check the depth of the expression.
Connections received from the proxy port may not count towards total accepted connections, resulting in server crashes if the total number of connections exceeds available resources. This only applies to connections accepted from the proxy port, pending the proxy protocol header.
Inserting certain large documents into a replica set could lead to replica set secondaries not being able to fetch the oplog from the primary. This could stall replication inside the replica set leading to server crash.
The internal locking mechanism of the MongoDB server uses an internal encoding of the resources in order to choose what lock to take. Collections may inadvertently collide with one another in this representation causing unavailability between them due to conflicting locks.
Mismatched length fields in Zlib compressed protocol headers may allow a read of uninitialized heap memory by an unauthenticated client. This issue affects all MongoDB Server v7.0 prior to 7.0.28 versions, MongoDB Server v8.0 versions prior to 8.0.17, MongoDB Server v8.2 versions prior to 8.2.3, MongoDB Server v6.0 versions prior to 6.0.27, MongoDB Server v5.0 versions prior to 5.0.32, MongoDB Server v4.4 versions prior to 4.4.30, MongoDB Server v4.2 versions greater than or equal to 4.2.0, MongoDB Server v4.0 versions greater than or equal to 4.0.0, and MongoDB Server v3.6 versions greater than or equal to 3.6.0.
A post-authentication flaw in the network two-phase commit protocol used for cross-shard transactions in MongoDB Server may lead to logical data inconsistencies under specific conditions which are not predictable and exist for a very short period of time. This error can cause the transaction coordination logic to misinterpret the transaction as committed, resulting in inconsistent state on those shards. This may lead to low integrity and availability impact.
This issue impacts MongoDB Server v8.0 versions prior to 8.0.16, MongoDB Server v7.0 versions prior to 7.0.26 and MongoDB server v8.2 versions prior to 8.2.2.
A user with access to the cluster with a limited set of privilege actions may be able to terminate queries that are being executed by other users. This may cause a denial of service by preventing a fraction of queries from successfully completing. This issue affects MongoDB Server v7.0 versions prior to 7.0.26 and MongoDB Server v8.0 versions prior to 8.0.14
MongoDB Server may experience an invariant failure during batched delete operations when handling documents. The issue arises when the server mistakenly assumes the presence of multiple documents in a batch based solely on document size exceeding BSONObjMaxSize. This issue affects MongoDB Server v7.0 versions prior to 7.0.26, MongoDB Server v8.0 versions prior to 8.0.13, and MongoDB Server v8.1 versions prior to 8.1.2
Clients may successfully perform a TLS handshake with a MongoDB server despite presenting a client certificate not aligning with the documented Extended Key Usage (EKU) requirements. A certificate that specifies extendedKeyUsage but is missing extendedKeyUsage = clientAuth may still be successfully authenticated via the TLS handshake as a client. This issue is specific to MongoDB servers running on Windows or Apple as the expected validation behavior functions correctly on Linux systems.
Additionally, MongoDB servers may successfully establish egress TLS connections with servers that present server certificates not aligning with the documented Extended Key Usage (EKU) requirements. A certificate that specifies extendedKeyUsage but is missing extendedKeyUsage = serverAuth may still be successfully authenticated via the TLS handshake as a server. This issue is specific to MongoDB servers running on Apple as the expected validation behavior functions correctly on both Linux and Windows systems.
This vulnerability affects MongoDB Server v7.0 versions prior to 7.0.26, MongoDB Server v8.0 versions prior to 8.0.16 and MongoDB Server v8.2 versions prior to 8.2.2
Inconsistent object size validation in time series processing logic may result in later processing of oversized BSON documents leading to an assert failing and process termination.
This issue impacts MongoDB Server v7.0 versions prior to 7.0.26, v8.0 versions prior to 8.0.16 and MongoDB server v8.2 versions prior to 8.2.1.
