CVE-2026-66391 (CVSS 6.5)

Description

Use of Insufficiently Random Values, Protection Mechanism Failure vulnerability in Apache Wicket. This issue affects Apache Wicket: from 9.0.0 through 9.23.0, from 10.0.0 through 10.9.0. Users are recommended to upgrade to version 10.10.0, which fixes the issue.

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CVSS v3.1 Score

6.5

MEDIUM

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

EPSS — Exploit Prediction

0.0020

Probability of exploitation

0.09%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-330 CWE-330

CWE-693 CWE-693

References

Other References

https://lists.apache.org/thread/hfzcgjsbmmthzchtb8b8nv47d95scmqk http://www.openwall.com/lists/oss-security/2026/07/27/5

Frequently Asked Questions

What is CVE-2026-66391? +

Use of Insufficiently Random Values, Protection Mechanism Failure vulnerability in Apache Wicket. This issue affects Apache Wicket: from 9.0.0 through 9.23.0, from 10.0.0 through 10.9.0. Users are recommended to upgrade to version 10.10.0, which fixes the issue. It has a CVSS v3.1 base score of 6.5 (MEDIUM).

How severe is CVE-2026-66391? +

CVE-2026-66391 has a CVSS v3.1 score of 6.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance. The EPSS score is 0.0020, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-66391? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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