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TI-2021-06275 Aliases CVE-2021-23937GHSA-hmhg-95wh-r699

DNS proxy and possible amplification attack

Priority MEDIUM 40CWE-200Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Information disclosure
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and GitHub. Impact type from CWE-200.

Summary

A DNS proxy and possible amplification attack vulnerability in WebClientInfo of Apache Wicket allows an attacker to trigger arbitrary DNS lookups from the server when the X-Forwarded-For header is not properly sanitized. This DNS lookup can be engineered to overload an internal DNS server or to slow down request processing of the Apache Wicket application causing a possible denial of service on either the internal infrastructure or the web application itself. This issue affects Apache Wicket Apache Wicket 9.x version 9.2.0 and prior versions; Apache Wicket 8.x version 8.11.0 and prior versions; Apache Wicket 7.x version 7.17.0 and prior versions and Apache Wicket 6.x version 6.2.0 and later versions.

Why it matters now

EPSS 0.0426 91st percentileScored 2026-11-07
Fix Fixed org.apache.wicket:wicket-core (Maven): 9.3.0, 8.12.0, 7.18.0

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
ApacheApache WicketApache Wicket 9.x – 9.2.0; Apache Wicket 8.x – 8.11.0; Apache Wicket 7.x – 7.17.0; 6.2.0 and later—No fix listedCNA
—org.apache.wicket:wicket-core (Maven)9.0.0 to before 9.3.09.3.0Patch availableGHSA-hmhg-95wh-r699
—org.apache.wicket:wicket-core (Maven)8.0.0 to before 8.12.08.12.0Patch availableGHSA-hmhg-95wh-r699
—org.apache.wicket:wicket-core (Maven)before 7.18.07.18.0Patch availableGHSA-hmhg-95wh-r699
  • Apache Wicket VendorApache Affected Apache Wicket 9.x – 9.2.0; Apache Wicket 8.x – 8.11.0; Apache Wicket 7.x – 7.17.0; 6.2.0 and later Fixed in — No fix listed CNA
  • org.apache.wicket:wicket-core (Maven) Vendor— Affected 9.0.0 to before 9.3.0 Fixed in 9.3.0 Patch available GHSA-hmhg-95wh-r699
  • org.apache.wicket:wicket-core (Maven) Vendor— Affected 8.0.0 to before 8.12.0 Fixed in 8.12.0 Patch available GHSA-hmhg-95wh-r699
  • org.apache.wicket:wicket-core (Maven) Vendor— Affected before 7.18.0 Fixed in 7.18.0 Patch available GHSA-hmhg-95wh-r699

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:apache:wicket:*:*:*:*:*:*:*:*6.0.0 – 6.2.0; 7.0.0 – 7.17.0; 8.0.0 – 8.11.0; 9.0.0 – 9.2.0VulnerableApache
  • cpe:2.3:a:apache:wicket:*:*:*:*:*:*:*:* Versions 6.0.0 – 6.2.0; 7.0.0 – 7.17.0; 8.0.0 – 8.11.0; 9.0.0 – 9.2.0 Vulnerable ·Apache

Remediation

  • Fix · GHSA-hmhg-95wh-r699 org.apache.wicket:wicket-core (Maven) Fixed in 9.3.0 Advisory →
  • Fix · GHSA-hmhg-95wh-r699 org.apache.wicket:wicket-core (Maven) Fixed in 8.12.0 Advisory →
  • Fix · GHSA-hmhg-95wh-r699 org.apache.wicket:wicket-core (Maven) Fixed in 7.18.0 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-23937
  2. 2026-10-03 Alias added: GHSA-hmhg-95wh-r699

References

Advisory 2

Other 12

  • TI-2016-05834 The DiskFileItem class in Apache Wicket 6.x before 6.25.0 and 1.5.x before 1.5.17 allows… CVSS 3.0CRITICAL 9.1
  • TI-2026-28853 Apache Wicket: possible session fixation using AuthenticatedWebSession CVSS 3.1CRITICAL 9.1
  • TI-2024-24295 Apache Wicket: Remote code execution via XSLT injection CVSS 3.1CRITICAL 9.8
  • TI-2026-49926 Apache Wicket: Configured file upload limits are not enforced when the multipart request has already been parsed CVSS 3.1HIGH 7.5
  • TI-2016-05847 Cross-site request forgery in Apache Wicket CVSS 3.0HIGH 8.8
  • TI-2026-31747 Apache Wicket: crafted URLs can bypass PackageResourceGuard CVSS 3.1HIGH 7.5
See all 32 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences