{"schemaVersion":3,"id":"CVE-2021-23937","aliases":["GHSA-hmhg-95wh-r699"],"status":"published","duplicateOf":null,"title":null,"description":"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.","dates":{"published":"2021-05-25T08:05:10.000Z","modified":"2024-08-03T19:14:09.890Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":7.5,"severity":"high","version":"3.1","versionLabel":"v3.1","source":"NVD","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","computed":false,"selection":"backend-summary"},"metrics":[{"version":"3.1","versionLabel":"v3.1","source":"OSV · 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{"date":"2026-10-15T00:00:00.000Z","score":0.0426,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.0426,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.0426,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.0426,"percentile":0.90945}]},"kev":{"state":"not-listed","entries":[],"listedCount":0,"totalCatalogs":3,"catalogs":[{"source":"cisa","label":"CISA","listed":false,"entry":null},{"source":"enisa","label":"ENISA","listed":false,"entry":null},{"source":"circl","label":"CIRCL","listed":false,"entry":null}]},"ransomware":{"state":"none-recorded","sources":[]},"exploits":[],"exploitCount":0,"weaknesses":[{"id":"CWE-200","name":"Exposure 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