CVE-2024-27309: kafka Auth Bypass — Fix

Description

While an Apache Kafka cluster is being migrated from ZooKeeper mode to KRaft mode, in some cases ACLs will not be correctly enforced. Two preconditions are needed to trigger the bug: 1. The administrator decides to remove an ACL 2. The resource associated with the removed ACL continues to have two or more other ACLs associated with it after the removal. When those two preconditions are met, Kafka will treat the resource as if it had only one ACL associated with it after the removal, rather than the two or more that would be correct. The incorrect condition is cleared by removing all brokers in ZK mode, or by adding a new ACL to the affected resource. Once the migration is completed, there is no metadata loss (the ACLs all remain). The full impact depends on the ACLs in use. If only ALLOW ACLs were configured during the migration, the impact would be limited to availability impact. if DENY ACLs were configured, the impact could include confidentiality and integrity impact depending on the ACLs configured, as the DENY ACLs might be ignored due to this vulnerability during the migration period.

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CVSS v3.1 Score

7.4

HIGH

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N

Weakness Type (CWE)

CWE-863 Incorrect Authorization

Affected Products

Vendor	Product	Versions
apache	kafka	3.5.0 — 3.6.1

References

Advisories & Patches

https://lists.apache.org/thread/6536rmzyg076lzzdw2xdktvnz163mjpy https://lists.apache.org/thread/6536rmzyg076lzzdw2xdktvnz163mjpy

Other References

http://www.openwall.com/lists/oss-security/2024/04/12/3 https://security.netapp.com/advisory/ntap-20240705-0002/ http://www.openwall.com/lists/oss-security/2024/04/12/3 https://security.netapp.com/advisory/ntap-20240705-0002/

Frequently Asked Questions

What is CVE-2024-27309? +

While an Apache Kafka cluster is being migrated from ZooKeeper mode to KRaft mode, in some cases ACLs will not be correctly enforced. Two preconditions are needed to trigger the bug: 1. The administrator decides to remove an ACL 2. The resource associated with the removed ACL continues to have two or more other ACLs associated with it after the removal. When those two preconditions are met, Kafka will treat the resource as if it had only one ACL associated with it after the removal, rather than the two or more that would be correct. The incorrect condition is cleared by removing all brokers in ZK mode, or by adding a new ACL to the affected resource. Once the migration is completed, there is no metadata loss (the ACLs all remain). The full impact depends on the ACLs in use. If only ALLOW ACLs were configured during the migration, the impact would be limited to availability impact. if DENY ACLs were configured, the impact could include confidentiality and integrity impact depending on the ACLs configured, as the DENY ACLs might be ignored due to this vulnerability during the migration period. It has a CVSS v3.1 base score of 7.4 (HIGH).

How severe is CVE-2024-27309? +

CVE-2024-27309 has a CVSS v3.1 score of 7.4 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

What products are affected by CVE-2024-27309? +

CVE-2024-27309 affects products from apache, specifically: kafka. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2024-27309? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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