CVE-2021-20399

Severity: critical (CVSS 9.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.8% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-07-27 · updated 2026-06-17
Weakness: CWE-611

Description

IBM Qradar SIEM 7.3.0 to 7.3.3 Patch 8 and 7.4.0 to 7.4.3 GA is vulnerable to an XML External Entity Injection (XXE) attack when processing XML data. A remote attacker could exploit this vulnerability to expose sensitive information or consume memory resources. IBM X-Force ID: 196073.

Affected products

IBM QRadar SIEM: from 7.3.0 before 7.3.3; from 7.4.0 before 7.4.3; 7.3.3, 7.3.3-p1, 7.3.3-p2, 7.3.3-p3, 7.3.3-p4, 7.3.3-p5 (+7) — fixed in 7.3.3, 7.4.3

How to fix

Upgrade to a fixed version: IBM QRadar SIEM 7.3.3, 7.4.3. Check the vendor advisory for mitigations.

References

https://exchange.xforce.ibmcloud.com/vulnerabilities/196073
https://www.ibm.com/support/pages/node/6475263
https://exchange.xforce.ibmcloud.com/vulnerabilities/196073
https://www.ibm.com/support/pages/node/6475263

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