{"api_version":"1","generated_at":"2026-04-23T02:58:46+00:00","cve":"CVE-2021-28691","urls":{"html":"https://cve.report/CVE-2021-28691","api":"https://cve.report/api/cve/CVE-2021-28691.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2021-28691","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2021-28691"},"summary":{"title":"CVE-2021-28691","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.","state":"PUBLIC","assigner":"security@xen.org","published_at":"2021-06-29 12:15:00","updated_at":"2022-04-06 16:46:00"},"problem_types":["CWE-416"],"metrics":[],"references":[{"url":"https://security.gentoo.org/glsa/202107-30","name":"GLSA-202107-30","refsource":"GENTOO","tags":[],"title":"Xen: Multiple vulnerabilities (GLSA 202107-30) — Gentoo security","mime":"text/html","httpstatus":"200","archivestatus":"404"},{"url":"https://xenbits.xenproject.org/xsa/advisory-374.txt","name":"https://xenbits.xenproject.org/xsa/advisory-374.txt","refsource":"MISC","tags":[],"title":"","mime":"text/plain","httpstatus":"200","archivestatus":"404"},{"url":"https://security.netapp.com/advisory/ntap-20210805-0002/","name":"https://security.netapp.com/advisory/ntap-20210805-0002/","refsource":"CONFIRM","tags":[],"title":"CVE-2021-28691 Linux Kernel Vulnerability in NetApp Products | NetApp Product Security","mime":"text/html","httpstatus":"200","archivestatus":"404"},{"url":"https://www.cve.org/CVERecord?id=CVE-2021-28691","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-28691","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[{"source":"LEGACY","value":"Array","lang":""}],"nvd_cpes":[{"cve_year":"2021","cve_id":"28691","vulnerable":"1","versionEndIncluding":"","cpe1":"cpe","cpe2":"2.3","cpe3":"o","cpe4":"linux","cpe5":"linux_kernel","cpe6":"*","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"*","cpe12":"*","cpe13":"*"},{"cve_year":"2021","cve_id":"28691","vulnerable":"1","versionEndIncluding":"","cpe1":"cpe","cpe2":"2.3","cpe3":"a","cpe4":"netapp","cpe5":"cloud_backup","cpe6":"-","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"*","cpe12":"*","cpe13":"*"},{"cve_year":"2021","cve_id":"28691","vulnerable":"-1","versionEndIncluding":"","cpe1":"cpe","cpe2":"2.3","cpe3":"h","cpe4":"netapp","cpe5":"h300e","cpe6":"-","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"*","cpe12":"*","cpe13":"*"},{"cve_year":"2021","cve_id":"28691","vulnerable":"1","versionEndIncluding":"","cpe1":"cpe","cpe2":"2.3","cpe3":"o","cpe4":"netapp","cpe5":"h300e_firmware","cpe6":"-","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"*","cpe12":"*","cpe13":"*"},{"cve_year":"2021","cve_id":"28691","vulnerable":"-1","versionEndIncluding":"","cpe1":"cpe","cpe2":"2.3","cpe3":"h","cpe4":"netapp","cpe5":"h300s","cpe6":"-","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"*","cpe12":"*","cpe13":"*"},{"cve_year":"2021","cve_id":"28691","vulnerable":"1","versionEndIncluding":"","cpe1":"cpe","cpe2":"2.3","cpe3":"o","cpe4":"netapp","cpe5":"h300s_firmware","cpe6":"-","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"*","cpe12":"*","cpe13":"*"},{"cve_year":"2021","cve_id":"28691","vulnerable":"-1","versionEndIncluding":"","cpe1":"cpe","cpe2":"2.3","cpe3":"h","cpe4":"netapp","cpe5":"h410c","cpe6":"-","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"*","cpe12":"*","cpe13":"*"},{"cve_year":"2021","cve_id":"28691","vulnerable":"1","versionEndIncluding":"","cpe1":"cpe","cpe2":"2.3","cpe3":"o","cpe4":"netapp","cpe5":"h410c_firmware","cpe6":"-","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"*","cpe12":"*","cpe13":"*"},{"cve_year":"2021","cve_id":"28691","vulnerable":"-1","versionEndIncluding":"","cpe1":"cpe","cpe2":"2.3","cpe3":"h","cpe4":"netapp","cpe5":"h410s","cpe6":"-","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"*","cpe12":"*","cpe13":"*"},{"cve_year":"2021","cve_id":"28691","vulnerable":"1","versionEndIncluding":"","cpe1":"cpe","cpe2":"2.3","cpe3":"o","cpe4":"netapp","cpe5":"h410s_firmware","cpe6":"-","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"*","cpe12":"*","cpe13":"*"},{"cve_year":"2021","cve_id":"28691","vulnerable":"-1","versionEndIncluding":"","cpe1":"cpe","cpe2":"2.3","cpe3":"h","cpe4":"netapp","cpe5":"h500e","cpe6":"-","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"*","cpe12":"*","cpe13":"*"},{"cve_year":"2021","cve_id":"28691","vulnerable":"1","versionEndIncluding":"","cpe1":"cpe","cpe2":"2.3","cpe3":"o","cpe4":"netapp","cpe5":"h500e_firmware","cpe6":"-","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"*","cpe12":"*","cpe13":"*"},{"cve_year":"2021","cve_id":"28691","vulnerable":"-1","versionEndIncluding":"","cpe1":"cpe","cpe2":"2.3","cpe3":"h","cpe4":"netapp","cpe5":"h500s","cpe6":"-","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"*","cpe12":"*","cpe13":"*"},{"cve_year":"2021","cve_id":"28691","vulnerable":"1","versionEndIncluding":"","cpe1":"cpe","cpe2":"2.3","cpe3":"o","cpe4":"netapp","cpe5":"h500s_firmware","cpe6":"-","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"*","cpe12":"*","cpe13":"*"},{"cve_year":"2021","cve_id":"28691","vulnerable":"-1","versionEndIncluding":"","cpe1":"cpe","cpe2":"2.3","cpe3":"h","cpe4":"netapp","cpe5":"h700e","cpe6":"-","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"*","cpe12":"*","cpe13":"*"},{"cve_year":"2021","cve_id":"28691","vulnerable":"1","versionEndIncluding":"","cpe1":"cpe","cpe2":"2.3","cpe3":"o","cpe4":"netapp","cpe5":"h700e_firmware","cpe6":"-","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"*","cpe12":"*","cpe13":"*"},{"cve_year":"2021","cve_id":"28691","vulnerable":"-1","versionEndIncluding":"","cpe1":"cpe","cpe2":"2.3","cpe3":"h","cpe4":"netapp","cpe5":"h700s","cpe6":"-","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"*","cpe12":"*","cpe13":"*"},{"cve_year":"2021","cve_id":"28691","vulnerable":"1","versionEndIncluding":"","cpe1":"cpe","cpe2":"2.3","cpe3":"o","cpe4":"netapp","cpe5":"h700s_firmware","cpe6":"-","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"*","cpe12":"*","cpe13":"*"}],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[{"cve":"CVE-2021-28691","qid":"180071","title":"Debian Security Update for linux (CVE-2021-28691)"},{"cve":"CVE-2021-28691","qid":"198436","title":"Ubuntu Security Notification for Linux kernel (OEM) vulnerabilities (USN-5015-1) (Sequoia)"},{"cve":"CVE-2021-28691","qid":"198465","title":"Ubuntu Security Notification for Linux kernel Vulnerabilities (USN-5046-1)"},{"cve":"CVE-2021-28691","qid":"198468","title":"Ubuntu Security Notification for Linux kernel Vulnerabilities (USN-5050-1)"},{"cve":"CVE-2021-28691","qid":"353158","title":"Amazon Linux Security Advisory for kernel : ALAS2KERNEL-5.10-2022-002"},{"cve":"CVE-2021-28691","qid":"710038","title":"Gentoo Linux Xen Multiple vulnerabilities (GLSA 202107-30)"},{"cve":"CVE-2021-28691","qid":"900084","title":"CBL-Mariner Linux Security Update for kernel 5.10.52.1"},{"cve":"CVE-2021-28691","qid":"900304","title":"CBL-Mariner Linux Security Update for kernel 5.10.57.1"},{"cve":"CVE-2021-28691","qid":"900319","title":"CBL-Mariner Linux Security Update for kernel 5.10.60.1"},{"cve":"CVE-2021-28691","qid":"900887","title":"Common Base Linux Mariner (CBL-Mariner) Security Update for kernel (6537-1)"},{"cve":"CVE-2021-28691","qid":"903024","title":"Common Base Linux Mariner (CBL-Mariner) Security Update for kernel (4375)"},{"cve":"CVE-2021-28691","qid":"906029","title":"Common Base Linux Mariner (CBL-Mariner) Security Update for kernel (4375-1)"}]},"source_records":{"cve_program":{"CVE_data_meta":{"ASSIGNER":"security@xen.org","ID":"CVE-2021-28691","STATE":"PUBLIC"},"affects":{"vendor":{"vendor_data":[{"product":{"product_data":[{"product_name":"Linux","version":{"version_data":[{"version_affected":"?<","version_value":"4.12"},{"version_affected":">=","version_value":"5.5.0"},{"version_affected":"!>","version_value":"5.12.2"}]}}]},"vendor_name":"Linux"}]}},"configuration":{"configuration_data":{"description":{"description_data":[{"lang":"eng","value":"Systems using Linux version 5.5 or newer are vulnerable."}]}}},"credit":{"credit_data":{"description":{"description_data":[{"lang":"eng","value":"This issue was discovered by Michael Brown of iPXE and diagnosed by\nOlivier Benjamin, Michael Kurth and Martin Mazein of AWS."}]}}},"data_format":"MITRE","data_type":"CVE","data_version":"4.0","description":{"description_data":[{"lang":"eng","value":"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."}]},"impact":{"impact_data":{"description":{"description_data":[{"lang":"eng","value":"A malicious or buggy frontend driver can trigger a dom0 crash.\nPrivilege escalation and information leaks cannot be ruled out."}]}}},"problemtype":{"problemtype_data":[{"description":[{"lang":"eng","value":"unknown"}]}]},"references":{"reference_data":[{"url":"https://xenbits.xenproject.org/xsa/advisory-374.txt","refsource":"MISC","name":"https://xenbits.xenproject.org/xsa/advisory-374.txt"},{"refsource":"GENTOO","name":"GLSA-202107-30","url":"https://security.gentoo.org/glsa/202107-30"},{"refsource":"CONFIRM","name":"https://security.netapp.com/advisory/ntap-20210805-0002/","url":"https://security.netapp.com/advisory/ntap-20210805-0002/"}]},"workaround":{"workaround_data":{"description":{"description_data":[{"lang":"eng","value":"On x86 running only HVM guests with emulated network cards will avoid the\nissue.  There's however no option in the upstream toolstack to offer only\nemulated network cards to guests."}]}}}},"nvd":{"publishedDate":"2021-06-29 12:15:00","lastModifiedDate":"2022-04-06 16:46:00","problem_types":["CWE-416"],"metrics":{"baseMetricV3":{"cvssV3":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH","baseScore":7.8,"baseSeverity":"HIGH"},"exploitabilityScore":1.8,"impactScore":5.9},"baseMetricV2":{"cvssV2":{"version":"2.0","vectorString":"AV:L/AC:L/Au:N/C:P/I:P/A:P","accessVector":"LOCAL","accessComplexity":"LOW","authentication":"NONE","confidentialityImpact":"PARTIAL","integrityImpact":"PARTIAL","availabilityImpact":"PARTIAL","baseScore":4.6},"severity":"MEDIUM","exploitabilityScore":3.9,"impactScore":6.4,"acInsufInfo":false,"obtainAllPrivilege":false,"obtainUserPrivilege":false,"obtainOtherPrivilege":false,"userInteractionRequired":false}},"configurations":{"CVE_data_version":"4.0","nodes":[{"operator":"OR","children":[],"cpe_match":[{"vulnerable":true,"cpe23Uri":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.5.0","versionEndExcluding":"5.12.2","cpe_name":[]}]},{"operator":"OR","children":[],"cpe_match":[{"vulnerable":true,"cpe23Uri":"cpe:2.3:a:netapp:cloud_backup:-:*:*:*:*:*:*:*","cpe_name":[]}]},{"operator":"AND","children":[{"operator":"OR","children":[],"cpe_match":[{"vulnerable":true,"cpe23Uri":"cpe:2.3:o:netapp:h410c_firmware:-:*:*:*:*:*:*:*","cpe_name":[]}]},{"operator":"OR","children":[],"cpe_match":[{"vulnerable":false,"cpe23Uri":"cpe:2.3:h:netapp:h410c:-:*:*:*:*:*:*:*","cpe_name":[]}]}],"cpe_match":[]},{"operator":"AND","children":[{"operator":"OR","children":[],"cpe_match":[{"vulnerable":true,"cpe23Uri":"cpe:2.3:o:netapp:h300s_firmware:-:*:*:*:*:*:*:*","cpe_name":[]}]},{"operator":"OR","children":[],"cpe_match":[{"vulnerable":false,"cpe23Uri":"cpe:2.3:h:netapp:h300s:-:*:*:*:*:*:*:*","cpe_name":[]}]}],"cpe_match":[]},{"operator":"AND","children":[{"operator":"OR","children":[],"cpe_match":[{"vulnerable":true,"cpe23Uri":"cpe:2.3:o:netapp:h500s_firmware:-:*:*:*:*:*:*:*","cpe_name":[]}]},{"operator":"OR","children":[],"cpe_match":[{"vulnerable":false,"cpe23Uri":"cpe:2.3:h:netapp:h500s:-:*:*:*:*:*:*:*","cpe_name":[]}]}],"cpe_match":[]},{"operator":"AND","children":[{"operator":"OR","children":[],"cpe_match":[{"vulnerable":true,"cpe23Uri":"cpe:2.3:o:netapp:h700s_firmware:-:*:*:*:*:*:*:*","cpe_name":[]}]},{"operator":"OR","children":[],"cpe_match":[{"vulnerable":false,"cpe23Uri":"cpe:2.3:h:netapp:h700s:-:*:*:*:*:*:*:*","cpe_name":[]}]}],"cpe_match":[]},{"operator":"AND","children":[{"operator":"OR","children":[],"cpe_match":[{"vulnerable":true,"cpe23Uri":"cpe:2.3:o:netapp:h300e_firmware:-:*:*:*:*:*:*:*","cpe_name":[]}]},{"operator":"OR","children":[],"cpe_match":[{"vulnerable":false,"cpe23Uri":"cpe:2.3:h:netapp:h300e:-:*:*:*:*:*:*:*","cpe_name":[]}]}],"cpe_match":[]},{"operator":"AND","children":[{"operator":"OR","children":[],"cpe_match":[{"vulnerable":true,"cpe23Uri":"cpe:2.3:o:netapp:h500e_firmware:-:*:*:*:*:*:*:*","cpe_name":[]}]},{"operator":"OR","children":[],"cpe_match":[{"vulnerable":false,"cpe23Uri":"cpe:2.3:h:netapp:h500e:-:*:*:*:*:*:*:*","cpe_name":[]}]}],"cpe_match":[]},{"operator":"AND","children":[{"operator":"OR","children":[],"cpe_match":[{"vulnerable":true,"cpe23Uri":"cpe:2.3:o:netapp:h700e_firmware:-:*:*:*:*:*:*:*","cpe_name":[]}]},{"operator":"OR","children":[],"cpe_match":[{"vulnerable":false,"cpe23Uri":"cpe:2.3:h:netapp:h700e:-:*:*:*:*:*:*:*","cpe_name":[]}]}],"cpe_match":[]},{"operator":"AND","children":[{"operator":"OR","children":[],"cpe_match":[{"vulnerable":true,"cpe23Uri":"cpe:2.3:o:netapp:h410s_firmware:-:*:*:*:*:*:*:*","cpe_name":[]}]},{"operator":"OR","children":[],"cpe_match":[{"vulnerable":false,"cpe23Uri":"cpe:2.3:h:netapp:h410s:-:*:*:*:*:*:*:*","cpe_name":[]}]}],"cpe_match":[]}]}},"legacy_mitre":{"record":{"CveYear":"2021","CveId":"28691","Ordinal":"203867","Title":"CVE-2021-28691","CVE":"CVE-2021-28691","Year":"2021"},"notes":[{"CveYear":"2021","CveId":"28691","Ordinal":"1","NoteData":"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.","Type":"Description","Title":null},{"CveYear":"2021","CveId":"28691","Ordinal":"2","NoteData":"2021-06-29","Type":"Other","Title":"Published"},{"CveYear":"2021","CveId":"28691","Ordinal":"3","NoteData":"2021-08-05","Type":"Other","Title":"Modified"}]}}}