CVE-2021-31522 Apache Kylin unsafe class loading

What is CVE-2021-31522?

CVE-2021-31522 is a critical code injection vulnerability in Apache Kylin, published on 6 Jan 2022. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

Kylin can receive user input and load any class through Class.forName(...). This issue affects Apache Kylin 2 version 2.6.6 and prior versions; Apache Kylin 3 version 3.1.2 and prior versions; Apache Kylin 4 version 4.0.0 and prior versions.

Weakness: CWE-470

Which versions are affected by CVE-2021-31522?

4 open source packages ship an affected version, including org.apache.kylin:kylin. It affects 1 product.

Products include Apache Kylin.

How do I fix CVE-2021-31522?

Upgrade org.apache.kylin:kylin to a fixed version for your release line: 3.1.3 or 4.0.1.

Upgrade, and never evaluate templates, expressions or code built from user input. More about Code injection.

Is CVE-2021-31522 being exploited?

There is no known exploitation of CVE-2021-31522 in the wild and no public exploit code.

Other vulnerabilities in Apache Kylin

• CVE-2020-1956 Apache Kylin OS Command Injection Exploited High 8.8
• CVE-2026-62390 Apache Kylin: SQL Injection Vulnerability in Catalog Cache Refresh API Critical 9.8
• CVE-2022-44621 Apache Kylin: Command injection by Diagnosis Controller Critical 9.8
• CVE-2022-24697 Apache Kylin vulnerable to remote code execution Critical 9.8
• CVE-2021-45456 Command injection Critical 9.8

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-q656-g2x3-8cgh.