CVE-2021-43799

Zulip is an open-source team collaboration tool. Zulip Server installs RabbitMQ for internal message passing. In versions of Zulip Server prior to 4.9, the initial installation (until first reboot, or restart of RabbitMQ) does not successfully limit the default ports which RabbitMQ opens; this includes port 25672, the RabbitMQ distribution port, which is used as a management port. RabbitMQ's default "cookie" which protects this port is generated using a weak PRNG, which limits the entropy of the password to at most 36 bits; in practicality, the seed for the randomizer is biased, resulting in approximately 20 bits of entropy. If other firewalls (at the OS or network level) do not protect port 25672, a remote attacker can brute-force the 20 bits of entropy in the "cookie" and leverage it for arbitrary execution of code as the rabbitmq user. They can also read all data which is sent through RabbitMQ, which includes all message traffic sent by users. Version 4.9 contains a patch for this vulnerability. As a workaround, ensure that firewalls prevent access to ports 5672 and 25672 from outside the Zulip server.
Configurations

Configuration 1 (hide)

cpe:2.3:a:zulip:zulip:*:*:*:*:*:*:*:*

History

21 Nov 2024, 06:29

Type Values Removed Values Added
References () https://github.com/gteissier/erl-matter - Third Party Advisory () https://github.com/gteissier/erl-matter - Third Party Advisory
References () https://github.com/zulip/zulip/commit/a5496f4098e3998c9b84e8dc564aa983d6cdf6e8 - Patch, Third Party Advisory () https://github.com/zulip/zulip/commit/a5496f4098e3998c9b84e8dc564aa983d6cdf6e8 - Patch, Third Party Advisory
References () https://github.com/zulip/zulip/releases/tag/4.9 - Release Notes, Third Party Advisory () https://github.com/zulip/zulip/releases/tag/4.9 - Release Notes, Third Party Advisory
References () https://github.com/zulip/zulip/security/advisories/GHSA-p663-wxvv-2fjp - Third Party Advisory () https://github.com/zulip/zulip/security/advisories/GHSA-p663-wxvv-2fjp - Third Party Advisory
CVSS v2 : 5.0
v3 : 9.8
v2 : 5.0
v3 : 8.6

Information

Published : 2022-01-25 21:15

Updated : 2024-11-21 06:29


NVD link : CVE-2021-43799

Mitre link : CVE-2021-43799

CVE.ORG link : CVE-2021-43799


JSON object : View

Products Affected

zulip

  • zulip
CWE
CWE-338

Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG)