{"cve":{"cve_id":"CVE-2026-5947","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":0.01387,"epss_percentile":0.70207,"epss_as_of":"2026-08-26","description":"Undefined behavior may result due to a race condition leading to a use-after-free violation.  If BIND receives an incoming DNS message signed with SIG(0), it begins work to validate that signature.  If, during that validation, the \"recursive-clients\" limit is reached (as would occur during a query flood), and that same DNS message is discarded per the limit, there is a brief window of time while the SIG(0) validation may attempt to read the now-discarded DNS message.\nThis issue affects BIND 9 versions 9.20.0 through 9.20.22, 9.21.0 through 9.21.21, and 9.20.9-S1 through 9.20.22-S1.\nBIND 9 versions 9.18.28 through 9.18.49 and 9.18.28-S1 through 9.18.49-S1 are NOT affected.","published_at":"2026-05-20T13:10:11.873000Z","last_modified_at":"2026-08-24T13:19:13.360000Z","cvss_v3_score":7.5,"cvss_v3_vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","cvss_v3_severity":"HIGH","cvss_v4_score":null,"cvss_v4_vector":null,"cvss_v4_severity":null,"ssvc_decision":null,"ssvc_exploitation":"none","ssvc_automatable":true,"ssvc_technical_impact":"partial","cwes":["CWE-362","CWE-416","CWE-367"],"nvd_references":["https://kb.isc.org/docs/cve-2026-5947","https://downloads.isc.org/isc/bind9/9.20.23","https://downloads.isc.org/isc/bind9/9.21.22"],"vuln_status":"Modified","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":"2026-08-24T19:35:50.286612Z"},"effective_severity":"HIGH","badges":[],"impact_analysis":[],"cvss_v3_decoded":{"version":"3.1","metrics":[{"metric":"AV","name":"Attack Vector","value":"N","value_label":"Network"},{"metric":"AC","name":"Attack Complexity","value":"L","value_label":"Low"},{"metric":"PR","name":"Privileges Required","value":"N","value_label":"None"},{"metric":"UI","name":"User Interaction","value":"N","value_label":"None"},{"metric":"S","name":"Scope","value":"U","value_label":"Unchanged"},{"metric":"C","name":"Confidentiality","value":"N","value_label":"None"},{"metric":"I","name":"Integrity","value":"N","value_label":"None"},{"metric":"A","name":"Availability","value":"H","value_label":"High"}]},"cvss_v4_decoded":{"version":null,"metrics":[]},"affected":[{"vendor_slug":"isc","vendor_name":"ISC","product_slug":"bind","product_name":"BIND","version_start":"9.20.0","version_start_inclusive":true,"version_end":"9.20.23","version_end_inclusive":false,"cpe23_uri":"cpe:2.3:a:isc:bind:*:*:*:*:-:*:*:*"},{"vendor_slug":"isc","vendor_name":"ISC","product_slug":"bind-9","product_name":"BIND 9","version_start":"9.20.0","version_start_inclusive":true,"version_end":"9.20.22","version_end_inclusive":true,"cpe23_uri":"cve5:isc:bind-9:9.20.0:9.20.22"},{"vendor_slug":"isc","vendor_name":"ISC","product_slug":"bind-9","product_name":"BIND 9","version_start":"9.21.0","version_start_inclusive":true,"version_end":"9.21.21","version_end_inclusive":true,"cpe23_uri":"cve5:isc:bind-9:9.21.0:9.21.21"},{"vendor_slug":"isc","vendor_name":"ISC","product_slug":"bind-9","product_name":"BIND 9","version_start":"9.20.9-S1","version_start_inclusive":true,"version_end":"9.20.22-S1","version_end_inclusive":true,"cpe23_uri":"cve5:isc:bind-9:9.20.9-S1:9.20.22-S1"},{"vendor_slug":"isc","vendor_name":"ISC","product_slug":"bind-9","product_name":"BIND 9","version_start":"9.18.28","version_start_inclusive":true,"version_end":"9.18.49","version_end_inclusive":true,"cpe23_uri":"cve5:isc:bind-9:9.18.28:9.18.49"},{"vendor_slug":"isc","vendor_name":"ISC","product_slug":"bind-9","product_name":"BIND 9","version_start":"9.18.28-S1","version_start_inclusive":true,"version_end":"9.18.49-S1","version_end_inclusive":true,"cpe23_uri":"cve5:isc:bind-9:9.18.28-S1:9.18.49-S1"}],"exploit_refs":[],"news":[],"references":[{"url":"https://kb.isc.org/docs/cve-2026-5947","source_type":"MISC","tags":[]},{"url":"https://downloads.isc.org/isc/bind9/9.20.23","source_type":"MISC","tags":[]},{"url":"https://downloads.isc.org/isc/bind9/9.21.22","source_type":"MISC","tags":[]}],"timeline":[{"type":"published","at":"2026-05-20T13:10:11.873000Z","label":"CVE published","source":null},{"type":"cvss_changed","at":"2026-06-28T17:56:01.087206Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"cvss_changed","at":"2026-06-28T17:56:01.087206Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"cvss_changed","at":"2026-06-28T17:56:01.087206Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"ssvc_changed","at":"2026-06-29T23:46:59.033383Z","label":"SSVC decision revised","source":"vulnrichment"},{"type":"ssvc_changed","at":"2026-06-29T23:46:59.033383Z","label":"SSVC decision revised","source":"vulnrichment"},{"type":"ssvc_changed","at":"2026-06-29T23:46:59.033383Z","label":"SSVC decision revised","source":"vulnrichment"}]}