CVE-2021-23463: XML External Entity (XXE) Injection

Severity: critical (CVSS 9.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 2.8% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2021-12-10 · updated 2026-06-17
Weakness: CWE-611

Description

The package com.h2database:h2 from 1.4.198 and before 2.0.202 are vulnerable to XML External Entity (XXE) Injection via the org.h2.jdbc.JdbcSQLXML class object, when it receives parsed string data from org.h2.jdbc.JdbcResultSet.getSQLXML() method. If it executes the getSource() method when the parameter is DOMSource.class it will trigger the vulnerability.

Affected products

com.h2database:h2: from 1.4.198 before 2.0.202 — fixed in 2.0.202

How to fix

Upgrade to a fixed version: com.h2database:h2 2.0.202. Check the vendor advisory for mitigations.

References

https://github.com/h2database/h2database/commit/d83285fd2e48fb075780ee95badee6f5a15ea7f8%23diff-008c2e4462609982199cd83e7cf6f1d6b41296b516783f6752c44b9f15dc7bc3
https://github.com/h2database/h2database/issues/3195
https://github.com/h2database/h2database/pull/3199
https://security.netapp.com/advisory/ntap-20230818-0010/
https://snyk.io/vuln/SNYK-JAVA-COMH2DATABASE-1769238
https://www.oracle.com/security-alerts/cpuapr2022.html
https://github.com/h2database/h2database/commit/d83285fd2e48fb075780ee95badee6f5a15ea7f8%23diff-008c2e4462609982199cd83e7cf6f1d6b41296b516783f6752c44b9f15dc7bc3
https://github.com/h2database/h2database/issues/3195
https://github.com/h2database/h2database/pull/3199
https://security.netapp.com/advisory/ntap-20230818-0010/
https://snyk.io/vuln/SNYK-JAVA-COMH2DATABASE-1769238
https://www.oracle.com/security-alerts/cpuapr2022.html

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