{"cve":{"cve_id":"CVE-2021-28691","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":0.00361,"epss_percentile":0.289,"epss_as_of":"2026-08-26","description":"Guest triggered use-after-free in Linux xen-netback A malicious or buggy network PV frontend can force Linux netback to disable the interface and terminate the receive kernel thread associated with queue 0 in response to the frontend sending a malformed packet. Such kernel thread termination will lead to a use-after-free in Linux netback when the backend is destroyed, as the kernel thread associated with queue 0 will have already exited and thus the call to kthread_stop will be performed against a stale pointer.","published_at":"2021-06-29T11:30:53Z","last_modified_at":"2026-08-26T17:57:08.287000Z","cvss_v3_score":7.8,"cvss_v3_vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","cvss_v3_severity":"HIGH","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":["CWE-416"],"nvd_references":["https://xenbits.xenproject.org/xsa/advisory-374.txt","https://security.gentoo.org/glsa/202107-30","https://security.netapp.com/advisory/ntap-20210805-0002/"],"vuln_status":"Analyzed","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":"2026-08-27T17:38:41.369924Z"},"effective_severity":"HIGH","badges":[],"impact_analysis":[],"cvss_v3_decoded":{"version":"3.1","metrics":[{"metric":"AV","name":"Attack Vector","value":"L","value_label":"Local"},{"metric":"AC","name":"Attack Complexity","value":"L","value_label":"Low"},{"metric":"PR","name":"Privileges Required","value":"L","value_label":"Low"},{"metric":"UI","name":"User Interaction","value":"N","value_label":"None"},{"metric":"S","name":"Scope","value":"U","value_label":"Unchanged"},{"metric":"C","name":"Confidentiality","value":"H","value_label":"High"},{"metric":"I","name":"Integrity","value":"H","value_label":"High"},{"metric":"A","name":"Availability","value":"H","value_label":"High"}]},"cvss_v4_decoded":{"version":null,"metrics":[]},"affected":[{"vendor_slug":"linux","vendor_name":"Linux","product_slug":"linux","product_name":"Linux","version_start":"unspecified","version_start_inclusive":true,"version_end":"4.12","version_end_inclusive":false,"cpe23_uri":"cve5:linux:linux:unspecified:4.12"},{"vendor_slug":"linux","vendor_name":"Linux","product_slug":"linux","product_name":"Linux","version_start":"5.5.0","version_start_inclusive":true,"version_end":"unspecified","version_end_inclusive":false,"cpe23_uri":"cve5:linux:linux:5.5.0:unspecified"},{"vendor_slug":"linux","vendor_name":"Linux","product_slug":"linux","product_name":"Linux","version_start":"next of 5.12.2","version_start_inclusive":true,"version_end":"unspecified","version_end_inclusive":false,"cpe23_uri":"cve5:linux:linux:next of 5.12.2:unspecified"},{"vendor_slug":"linux","vendor_name":"Linux","product_slug":"linux-kernel","product_name":"Linux kernel","version_start":"5.5.0","version_start_inclusive":true,"version_end":"5.10.43","version_end_inclusive":false,"cpe23_uri":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*"},{"vendor_slug":"netapp","vendor_name":"NETAPP","product_slug":"cloud-backup","product_name":"cloud_backup","version_start":null,"version_start_inclusive":null,"version_end":null,"version_end_inclusive":null,"cpe23_uri":"cpe:2.3:a:netapp:cloud_backup:-:*:*:*:*:*:*:*"},{"vendor_slug":"netapp","vendor_name":"NETAPP","product_slug":"h300e-firmware","product_name":"h300e_firmware","version_start":null,"version_start_inclusive":null,"version_end":null,"version_end_inclusive":null,"cpe23_uri":"cpe:2.3:o:netapp:h300e_firmware:-:*:*:*:*:*:*:*"},{"vendor_slug":"netapp","vendor_name":"NETAPP","product_slug":"h300s-firmware","product_name":"h300s_firmware","version_start":null,"version_start_inclusive":null,"version_end":null,"version_end_inclusive":null,"cpe23_uri":"cpe:2.3:o:netapp:h300s_firmware:-:*:*:*:*:*:*:*"},{"vendor_slug":"netapp","vendor_name":"NETAPP","product_slug":"h410c-firmware","product_name":"h410c_firmware","version_start":null,"version_start_inclusive":null,"version_end":null,"version_end_inclusive":null,"cpe23_uri":"cpe:2.3:o:netapp:h410c_firmware:-:*:*:*:*:*:*:*"},{"vendor_slug":"netapp","vendor_name":"NETAPP","product_slug":"h410s-firmware","product_name":"h410s_firmware","version_start":null,"version_start_inclusive":null,"version_end":null,"version_end_inclusive":null,"cpe23_uri":"cpe:2.3:o:netapp:h410s_firmware:-:*:*:*:*:*:*:*"},{"vendor_slug":"netapp","vendor_name":"NETAPP","product_slug":"h500e-firmware","product_name":"h500e_firmware","version_start":null,"version_start_inclusive":null,"version_end":null,"version_end_inclusive":null,"cpe23_uri":"cpe:2.3:o:netapp:h500e_firmware:-:*:*:*:*:*:*:*"},{"vendor_slug":"netapp","vendor_name":"NETAPP","product_slug":"h500s-firmware","product_name":"h500s_firmware","version_start":null,"version_start_inclusive":null,"version_end":null,"version_end_inclusive":null,"cpe23_uri":"cpe:2.3:o:netapp:h500s_firmware:-:*:*:*:*:*:*:*"},{"vendor_slug":"netapp","vendor_name":"NETAPP","product_slug":"h700e-firmware","product_name":"h700e_firmware","version_start":null,"version_start_inclusive":null,"version_end":null,"version_end_inclusive":null,"cpe23_uri":"cpe:2.3:o:netapp:h700e_firmware:-:*:*:*:*:*:*:*"},{"vendor_slug":"netapp","vendor_name":"NETAPP","product_slug":"h700s-firmware","product_name":"h700s_firmware","version_start":null,"version_start_inclusive":null,"version_end":null,"version_end_inclusive":null,"cpe23_uri":"cpe:2.3:o:netapp:h700s_firmware:-:*:*:*:*:*:*:*"},{"vendor_slug":"netapp","vendor_name":"NETAPP","product_slug":"solidfire-baseboard-management-controller","product_name":"solidfire_baseboard_management_controller","version_start":null,"version_start_inclusive":null,"version_end":null,"version_end_inclusive":null,"cpe23_uri":"cpe:2.3:a:netapp:solidfire_baseboard_management_controller:-:*:*:*:*:*:*:*"}],"exploit_refs":[],"news":[],"references":[{"url":"https://xenbits.xenproject.org/xsa/advisory-374.txt","source_type":"MISC","tags":[]},{"url":"https://security.gentoo.org/glsa/202107-30","source_type":"MISC","tags":[]},{"url":"https://security.netapp.com/advisory/ntap-20210805-0002/","source_type":"MISC","tags":[]}],"timeline":[{"type":"published","at":"2021-06-29T11:30:53Z","label":"CVE 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