How severe is CVE-2021-31522?

CVE-2021-31522 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-31522 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (85th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-31522?

CVE-2021-31522 primarily affects Apache Kylin. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-31522?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2021-31522 published?

CVE-2021-31522 was published on 2022-01-06 and last updated on 2026-06-17.

CVE-2021-31522

CVE-2021-31522 is a critical-severity vulnerability in Apache Kylin with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-470.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 3% (85th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-470
Affected product: Apache Kylin
Published: 2022-01-06
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2021-31522?: 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.
How severe is CVE-2021-31522?: CVE-2021-31522 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-31522 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (85th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-31522?: CVE-2021-31522 primarily affects Apache Kylin. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-31522?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2021-31522 published?: CVE-2021-31522 was published on 2022-01-06 and last updated on 2026-06-17.

References

Affected products (4)

cpe:2.3:a:apache:kylin:*:*:*:*:*:*:*:*
cpe:2.3:a:apache:kylin:4.0.0:-:*:*:*:*:*:*
cpe:2.3:a:apache:kylin:4.0.0:alpha:*:*:*:*:*:*
cpe:2.3:a:apache:kylin:4.0.0:beta:*:*:*:*:*:*

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