Affected: zeromq libzmq

In ZeroMQ before version 4.3.3, there is a denial-of-service vulnerability. Users with TCP transport public endpoints, even with CURVE/ZAP enabled, are impacted. If a raw TCP socket is opened and connected to an endpoint that is fully configured with CURVE/ZAP, legitimate clients will not be able to exchange any message. Handshakes complete successfully, and messages are delivered to the library, but the server application never receives them. This is patched in version 4.3.3.

Affected: Ubuntu:Pro:14.04:LTS: zeromq3, Ubuntu:Pro:16.04:LTS: zeromq3, Ubuntu:Pro:18.04:LTS: zeromq3, Ubuntu:Pro:20.04:LTS: zeromq3

It was discovered that ZeroMQ incorrectly handled certain application metadata. A remote attacker could use this issue to cause ZeroMQ to crash, or possibly execute arbitrary code. (CVE-2019-13132)

It was discovered that ZeroMQ mishandled certain network traffic. An unauthenticated attacker could use this vulnerability to cause a denial-of- service and prevent legitimate clients from communicating with ZeroMQ. (CVE-2020-15166)

It was discovered that ZeroMQ did not properly manage memory under certain circumstances. If a user or automated system were tricked into connecting to one or multiple compromised servers, a remote attacker could use this issue to cause a denial of service. (CVE-2021-20234)

It was discovered that ZeroMQ incorrectly handled memory when processing messages with arbitrarily large sizes under certain circumstances. A remote unauthenticated attacker could use this issue to cause a ZeroMQ server to crash, resulting in a denial of service, or possibly execute arbitrary code. This issue only affected Ubuntu 18.04 ESM and Ubuntu 20.04 ESM. (CVE-2021-20235)

It was discovered that ZeroMQ did not properly manage memory under certain circumstances. A remote unauthenticated attacker could use this issue to cause a ZeroMQ server to crash, resulting in a denial of service. This issue only affected Ubuntu 18.04 ESM and Ubuntu 20.04 ESM. (CVE-2021-20237)