CVE-2021-20453

Name: CVE-2021-20453
Creator: NVD / NIST
Published: 2021-04-20T12:15:12.853+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 8.2/10EPSS 2.56%

Last modified Jun 17, 2026

CVE-2021-20453 is a high-severity vulnerability rated 8.2/10 on the CVSS scale. IBM WebSphere Application Server 8.0, 8.5, and 9.0 is vulnerable to a 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. EPSS estimates a 2.56% chance of exploitation in the next 30 days.

Description

IBM WebSphere Application Server 8.0, 8.5, and 9.0 is vulnerable to a 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: 196648.

Metrics

CVSS 3.1

8.2/10

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

EPSS Probability

2.56%

83.1th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-611

Affected Software

Vendor	Product	Versions
Ibm	Websphere Application Server	>= 8.0.0.0, < 8.0.0.15
Ibm	Websphere Application Server	>= 8.5.0.0, < 8.5.5.20
Ibm	Websphere Application Server	>= 9.0.0.0, < 9.0.5.8

References

https://exchange.xforce.ibmcloud.com/vulnerabilities/196648VDB Entry, Vendor Advisory
https://www.ibm.com/support/pages/node/6445171Patch, Vendor Advisory
https://exchange.xforce.ibmcloud.com/vulnerabilities/196648VDB Entry, Vendor Advisory
https://www.ibm.com/support/pages/node/6445171Patch, Vendor Advisory

Timeline

Published: Apr 20, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-20453?

How severe is CVE-2021-20453?

CVE-2021-20453 has a CVSS score of 8.2/10 (HIGH severity). The EPSS model estimates a 2.56% probability of exploitation in the next 30 days.

How do I fix CVE-2021-20453?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-20453?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST