{"cve":{"cve_id":"CVE-2021-23937","is_kev":false,"kev_date_added":null,"kev_vendor_project":null,"kev_product":null,"kev_vulnerability_name":null,"kev_short_description":null,"kev_required_action":null,"kev_due_date":null,"kev_known_ransomware":null,"kev_notes":null,"kev_cwes":null,"epss_score":0.0426,"epss_percentile":0.89776,"epss_as_of":"2026-06-23","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.","published_at":"2021-05-25T08:05:10Z","last_modified_at":null,"cvss_v3_score":null,"cvss_v3_vector":null,"cvss_v3_severity":null,"cvss_v4_score":null,"cvss_v4_vector":null,"cvss_v4_severity":null,"ssvc_decision":null,"ssvc_exploitation":null,"ssvc_automatable":null,"ssvc_technical_impact":null,"cwes":null,"nvd_references":["https://lists.apache.org/thread.html/rc2ef22f90793e158cef65a7e370cdbca023c499d1403d65feeca870d%40%3Cusers.wicket.apache.org%3E","https://lists.apache.org/thread.html/r127c0c1f3cb71e5bc619ad1e4b898b97c49758d1f20a54042966473e%40%3Cannounce.wicket.apache.org%3E","https://lists.apache.org/thread.html/r127c0c1f3cb71e5bc619ad1e4b898b97c49758d1f20a54042966473e%40%3Cusers.wicket.apache.org%3E","https://lists.apache.org/thread.html/r8ccbd91b56ebf045d151bd4282bfeea7842a0698a0b76118fca8fe78%40%3Cdev.wicket.apache.org%3E"],"vuln_status":null,"trending_score":null,"is_trending":false,"has_trended":false,"trended_number_one":false,"trending_peak_score":null,"trending_peak_rank":null,"started_trending_at":null,"trended_number_one_at":null,"summary_generated":null,"summary_generated_at":null,"summary_model":null,"created_at":"2026-06-24T00:09:39.878444Z","updated_at":"2026-06-28T23:15:07.931472Z"},"effective_severity":null,"badges":[],"impact_analysis":[],"cvss_v3_decoded":{"version":null,"metrics":[]},"cvss_v4_decoded":{"version":null,"metrics":[]},"affected":[{"vendor_slug":"apache-software-foundation","vendor_name":"Apache Software Foundation","product_slug":"apache-wicket","product_name":"Apache Wicket","version_start":"Apache Wicket 9.x","version_start_inclusive":true,"version_end":"9.2.0","version_end_inclusive":true,"cpe23_uri":"cve5:apache-software-foundation:apache-wicket:Apache Wicket 9.x:9.2.0"},{"vendor_slug":"apache-software-foundation","vendor_name":"Apache Software Foundation","product_slug":"apache-wicket","product_name":"Apache Wicket","version_start":"Apache Wicket 8.x","version_start_inclusive":true,"version_end":"8.11.0","version_end_inclusive":true,"cpe23_uri":"cve5:apache-software-foundation:apache-wicket:Apache Wicket 8.x:8.11.0"},{"vendor_slug":"apache-software-foundation","vendor_name":"Apache Software Foundation","product_slug":"apache-wicket","product_name":"Apache Wicket","version_start":"Apache Wicket 7.x","version_start_inclusive":true,"version_end":"7.17.0","version_end_inclusive":true,"cpe23_uri":"cve5:apache-software-foundation:apache-wicket:Apache Wicket 7.x:7.17.0"},{"vendor_slug":"apache-software-foundation","vendor_name":"Apache Software Foundation","product_slug":"apache-wicket","product_name":"Apache Wicket","version_start":"6.2.0","version_start_inclusive":true,"version_end":"Apache Wicket 6.x*","version_end_inclusive":false,"cpe23_uri":"cve5:apache-software-foundation:apache-wicket:6.2.0:Apache Wicket 6.x*"}],"exploit_refs":[],"news":[],"references":[{"url":"https://lists.apache.org/thread.html/rc2ef22f90793e158cef65a7e370cdbca023c499d1403d65feeca870d%40%3Cusers.wicket.apache.org%3E","source_type":"MAILING_LIST","tags":["mailing-list"]},{"url":"https://lists.apache.org/thread.html/r127c0c1f3cb71e5bc619ad1e4b898b97c49758d1f20a54042966473e%40%3Cannounce.wicket.apache.org%3E","source_type":"MAILING_LIST","tags":["mailing-list"]},{"url":"https://lists.apache.org/thread.html/r127c0c1f3cb71e5bc619ad1e4b898b97c49758d1f20a54042966473e%40%3Cusers.wicket.apache.org%3E","source_type":"MAILING_LIST","tags":["mailing-list"]},{"url":"https://lists.apache.org/thread.html/r8ccbd91b56ebf045d151bd4282bfeea7842a0698a0b76118fca8fe78%40%3Cdev.wicket.apache.org%3E","source_type":"MAILING_LIST","tags":["mailing-list"]}],"timeline":[{"type":"published","at":"2021-05-25T08:05:10Z","label":"CVE published","source":null}]}