Linuxfoundation Nats-Server vulnerabilities

CVE-2025-30215 [CRITICAL] CVE-2025-30215: NATS-Server is a High-Performance server for NATS NATS-Server is a High-Performance server for NATS.io, the cloud and edge native messaging system. In versions starting from 2.2.0 but prior to 2.10.27 and 2.11.1, the management of JetStream assets happens with messages in the $JS. subject namespace in the system account; this is partially exposed into regular accounts to allow account holders to manage their assets. Some of the JS API requests were missi

CVE-2026-58253 [HIGH] CWE-287 CVE-2026-58253: NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Pr NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.14.0, 2.12.7, and 2.11.16, when no_auth_user was configured, a parser fast path intended for ordinary client connections could also apply to route or leafnode listeners, allowing an unauthenticated peer to bypass inter-server CONNECT authentica

CVE-2020-26892 [CRITICAL] CWE-798 CVE-2020-26892: The JWT library in NATS nats-server before 2.1.9 has Incorrect Access Control because of how expired The JWT library in NATS nats-server before 2.1.9 has Incorrect Access Control because of how expired credentials are handled.

CVE-2022-28357 [CRITICAL] CWE-22 CVE-2022-28357: NATS nats-server 2.2.0 through 2.7.4 allows directory traversal because of an unintended path to a m NATS nats-server 2.2.0 through 2.7.4 allows directory traversal because of an unintended path to a management action from a management account.

CVE-2022-24450 [HIGH] CWE-862 CVE-2022-24450: NATS nats-server before 2.7.2 has Incorrect Access Control. Any authenticated user can obtain the pr NATS nats-server before 2.7.2 has Incorrect Access Control. Any authenticated user can obtain the privileges of the System account by misusing the "dynamically provisioned sandbox accounts" feature.

CVE-2026-58250 [HIGH] CWE-476 CVE-2026-58250: NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Pr NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.12.8 and 2.11.17, an unauthenticated peer with network access to a leafnode listener with compression enabled could crash the server during the pre-authentication leafnode handshake by sending repeated leafnode INFO protocol messages before aut

CVE-2026-27889 [HIGH] CWE-190 CVE-2026-27889: NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. Star NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. Starting in version 2.2.0 and prior to versions 2.11.14 and 2.12.5, a missing sanity check on a WebSockets frame could trigger a server panic in the nats-server. This happens before authentication, and so is exposed to anyone who can connect to the websocke

CVE-2026-58210 [HIGH] CWE-400 CVE-2026-58210: NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Pr NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.14.3 and 2.12.12, an unauthenticated MQTT client could cause the server to retain large incomplete MQTT CONNECT packets before authentication completed, consuming server memory while the parser waited for the advertised MQTT packet length. This

CVE-2026-58208 [HIGH] CWE-248 CVE-2026-58208: NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Pr NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.14.3 and 2.12.12, a WebSocket listener could route requests for the MQTT-over-WebSocket path into MQTT handling even when MQTT was not configured, allowing an unauthenticated client with access to the WebSocket listener to reach uninitialized M

CVE-2026-33216 [HIGH] CWE-256 CVE-2026-33216: NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. Prio NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. Prior to versions 2.11.15 and 2.12.6, for MQTT deployments using usercodes/passwords: MQTT passwords are incorrectly classified as a non-authenticating identity statement (JWT) and exposed via monitoring endpoints. Versions 2.11.14 and 2.12.6 contain a fix.

CVE-2023-47090 [MEDIUM] CWE-863 CVE-2023-47090: NATS nats-server before 2.9.23 and 2.10.x before 2.10.2 has an authentication bypass. An implicit $G NATS nats-server before 2.9.23 and 2.10.x before 2.10.2 has an authentication bypass. An implicit $G user in an authorization block can sometimes be used for unauthenticated access, even when the intention of the configuration was for each user to have an account. The earliest affected version is 2.2.0.

CVE-2026-29785 [HIGH] CWE-476 CVE-2026-29785: NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. Prio NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. Prior to versions 2.11.14 and 2.12.5, if the nats-server has the "leafnode" configuration enabled (not default), then anyone who can connect can crash the nats-server by triggering a panic. This happens pre-authentication and requires that compression be en

CVE-2026-33218 [HIGH] CWE-20 CVE-2026-33218: NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. Prio NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. Prior to versions 2.11.15 and 2.12.6, a client which can connect to the leafnode port can crash the nats-server with a certain malformed message pre-authentication. Versions 2.11.15 and 2.12.6 contain a fix. As a workaround, disable leafnode support if not n

CVE-2026-27571 [HIGH] CWE-409 CVE-2026-27571: NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. The NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. The WebSockets handling of NATS messages handles compressed messages via the WebSockets negotiated compression. Prior to versions 2.11.2 and 2.12.3, the implementation bound the memory size of a NATS message but did not independently bound the memory consump

CVE-2023-46129 [HIGH] CWE-321 CVE-2023-46129: NATS.io is a high performance open source pub-sub distributed communication technology, built for th NATS.io is a high performance open source pub-sub distributed communication technology, built for the cloud, on-premise, IoT, and edge computing. The cryptographic key handling library, nkeys, recently gained support for encryption, not just for signing/authentication. This is used in nats-server 2.10 (Sep 2023) and newer for authentication callouts.

CVE-2026-58213 [HIGH] CWE-74 CVE-2026-58213: NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Pr NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.14.1 and 2.12.9, an MQTT client could include protocol control characters in subscription filters that were later forwarded as NATS protocol data to route or leafnode connections, corrupting the forwarded protocol stream and allowing injection o

CVE-2020-28466 [HIGH] CVE-2020-28466: This affects all versions of package github.com/nats-io/nats-server/server. Untrusted accounts are a This affects all versions of package github.com/nats-io/nats-server/server. Untrusted accounts are able to crash the server using configs that represent a service export/import cycles. Disclaimer from the maintainers: Running a NATS service which is exposed to untrusted users presents a heightened risk. Any remote execution flaw or equivalent seriousness, or

CVE-2019-13126 [HIGH] CWE-190 CVE-2019-13126: An integer overflow in NATS Server before 2.0.2 allows a remote attacker to crash the server by send An integer overflow in NATS Server before 2.0.2 allows a remote attacker to crash the server by sending a crafted request. If authentication is enabled, then the remote attacker must have first authenticated.

CVE-2021-3127 [HIGH] CWE-755 CVE-2021-3127: NATS Server 2.x before 2.2.0 and JWT library before 2.0.1 have Incorrect Access Control because Impo NATS Server 2.x before 2.2.0 and JWT library before 2.0.1 have Incorrect Access Control because Import Token bindings are mishandled.

CVE-2026-58251 [MEDIUM] CWE-285 CVE-2026-58251: NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Pr NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.14.0, 2.12.7, and 2.11.16, an authenticated user with subscription deny permissions could bypass a plain subject deny rule by using a queue subscription, because queue-specific deny evaluation could override the plain subject deny result when