Authorization bypass in Apache ZooKeeper

1) Authorization bypass through user-controlled key

EUVDB-ID: #VU83312

Risk: Medium

CVSSv4.0: 6.9 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2023-44981

CWE-ID: CWE-639 - Authorization Bypass Through User-Controlled Key

Exploit availability: No

Description

The vulnerability allows a remote attacker to bypass authorization process.

The vulnerability exists due to improper implementation of SASL Quorum Peer authentication. The instance part in SASL authentication ID, which is listed in zoo.cfg server list, is optional and if it's missing, the authorization check will be skipped. As a result an arbitrary endpoint could join the cluster and begin propagating counterfeit changes to the leader, essentially giving it complete read-write access to the data tree.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

ZooKeeper: 3.0.0 - 3.9.0

CPE2.3

• cpe:2.3:a:apache_foundation:zookeeper:3.0.0:*:*:*:*:*:*:*
• cpe:2.3:a:apache_foundation:zookeeper:3.0.1:rc0:*:*:*:*:*:*
• cpe:2.3:a:apache_foundation:zookeeper:3.0.1:*:*:*:*:*:*:*

External links

https://lists.apache.org/thread/wf0yrk84dg1942z1o74kd8nycg6pgm5b
https://www.openwall.com/lists/oss-security/2023/10/11/4
https://lists.debian.org/debian-lts-announce/2023/10/msg00029.html
https://www.debian.org/security/2023/dsa-5544

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

How the attacker can exploit this vulnerability?

The attacker would have to send a specially crafted request to the affected application in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.