CVE-2021-437998.6HighCWE-338

CVE-2021-43799: RabbitMQ exposes ports with weak default secrets in Zulip Server

zulip

Affected: zulip · Exploitation: possible (1 to 10%)

Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.

5.4%probability of exploitation in the next 30 days

92nd percentile

050100

Higher than 92% of scored CVEs

8.6HighCVSS 3.1

LowMediumHighCrit.

DescriptionCVE.org

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.

Affected products1

From the CVE record. A product or version that is not listed is unknown, not unaffected.

zulip · zulip< 4.9

On the Atlas

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Open the Atlas

Exploitation: Possible (1 to 10%). EPSS between 1% and 10%.
CISA KEV: Not listed
Public check: No public nuclei template
Weakness: Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG) · Cryptography
Vendor: zulip
Published: January 2022
Band: Possible (1 to 10%), January 2022

CoverageNo articles yet

No CyberSIXT article names CVE-2021-43799 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.