CVE-2026-42509: Apache Wicket: crafted strings can break out of the JavaScript sequence

Severity: medium (CVSS 6.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-05-06 · updated 2026-10-26
Weakness: CWE-79

Description

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in Apache Wicket. This issue affects Apache Wicket: from 8.0.0 through 8.17.0, 9.0.0, from 10.0.0 through 10.8.0. Users are recommended to upgrade to version 10.9.0, which fixes the issue.

Affected products

Apache Software Foundation Apache Wicket: from 8.0.0 through 8.17.0; from 9.0.0 through 9.22.0; from 10.0.0 before 10.9.0 — fixed in 10.9.0

How to fix

Upgrade to a fixed version: Apache Software Foundation Apache Wicket 10.9.0. Check the vendor advisory for mitigations.

References

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