{"id":"CVE-2021-21551","published":"2021-05-04T16:15:07Z","modified":"2026-06-17T03:35:45Z","title":"Dell dbutil Driver Insufficient Access Control Vulnerability","vendor":"Dell","product":"dbutil Driver","tier":"core","eol":null,"description":{"text":"Dell dbutil_2_3.sys driver contains an insufficient access control vulnerability which may lead to escalation of privileges, denial of service, or information disclosure. Local authenticated user access is required.","provenance":"source","from":"NVD"},"summary":{"text":"The flaw is an insufficient access control issue in the dbutil_2_3.sys driver, part of Dell's dbutil Driver product. An attacker who is an authenticated local user can exploit it to escalate privileges, cause denial of service, or disclose information, and no user interaction is needed.","provenance":"ai","model":"claude-haiku-5-5","generatedAt":"2026-10-23T07:10:45Z"},"cvss":{"score":7.8,"severity":"HIGH","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","provenance":"source","from":"NVD"},"epss":{"score":0.79628,"percentile":0.99605,"date":"2026-10-29","provenance":"source"},"kev":{"dateAdded":"2022-03-31","dueDate":"2022-04-21","ransomware":false,"requiredAction":"Apply updates per vendor instructions.","notes":"https://nvd.nist.gov/vuln/detail/CVE-2021-21551","provenance":"source"},"vulncheckKev":{"dateAdded":"2022-03-31","exploitedFirstSeen":"2022-03-31","ransomware":false,"evidence":[{"url":"https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json","date":"2022-03-31"},{"url":"https://www.virusbulletin.com/uploads/pdf/conference/vb2022/VB2022-Kalnai-Havranek.pdf","date":"2022-10-01"},{"url":"https://www.welivesecurity.com/wp-content/uploads/2023/02/eset_threat_report_t32022.pdf","date":"2023-02-08"},{"url":"https://documents-dds-ny.un.org/doc/UNDOC/GEN/N23/037/94/PDF/N2303794.pdf","date":"2023-03-07"},{"url":"https://www.mandiant.com/resources/blog/lightshift-and-lightshow","date":"2023-03-09"},{"url":"https://securityintelligence.com/posts/defensive-considerations-lazarus-fudmodule/","date":"2023-03-20"},{"url":"https://ics-cert.kaspersky.com/publications/reports/2023/03/24/apt-attacks-on-industrial-organizations-in-h2-2022/","date":"2023-03-24"},{"url":"https://redalert.nshc.net/2024/05/22/2023-activities-summary-of-sectora-groups-eng/","date":"2024-05-22"},{"url":"https://www.securityjoes.com/post/security-s-achilles-heel-vulnerable-drivers-on-the-prowl","date":"2024-07-15"}],"evidenceTotal":9,"provenance":"source"},"exploited":true,"otx":{"pulseCount":50,"pulses":[{"name":"Actively_Exploited_Kev | Oct 29, 2026","url":"https://otx.alienvault.com/pulse/6ae20c1db17e7057ae7d9ad1","created":"2026-10-28"},{"name":"Actively_Exploited_Kev | Oct 28, 2026","url":"https://otx.alienvault.com/pulse/6ae0ba7e0e2a97ff7b218819","created":"2026-10-27"},{"name":"Actively_Exploited_Kev | Oct 27, 2026","url":"https://otx.alienvault.com/pulse/6adf68b85c3e852f3c111d18","created":"2026-10-26"},{"name":"Actively_Exploited_Kev | Oct 24, 2026","url":"https://otx.alienvault.com/pulse/6adb740e397c3ad4799aa4cd","created":"2026-10-23"},{"name":"Actively_Exploited_Kev | Oct 23, 2026","url":"https://otx.alienvault.com/pulse/6ada236fcfba2dfa730ea482","created":"2026-10-22"},{"name":"Actively_Exploited_Kev | Oct 22, 2026","url":"https://otx.alienvault.com/pulse/6ad8d33a077cbb5cab524d80","created":"2026-10-21"},{"name":"Actively_Exploited_Kev | Oct 21, 2026","url":"https://otx.alienvault.com/pulse/6ad78130c4d1ac2be83a8b6d","created":"2026-10-20"},{"name":"Actively_Exploited_Kev | Oct 20, 2026","url":"https://otx.alienvault.com/pulse/6ad62f63c24a405a3423cc13","created":"2026-10-19"},{"name":"Actively_Exploited_Kev | Oct 19, 2026","url":"https://otx.alienvault.com/pulse/6ad4dda174e5797d0bd238b7","created":"2026-10-18"},{"name":"Actively_Exploited_Kev | Oct 18, 2026","url":"https://otx.alienvault.com/pulse/6ad38c22e1848f8189d1c121","created":"2026-10-17"}],"provenance":"machine"},"cwes":[{"id":"CWE-782","name":"Exposed IOCTL with Insufficient Access Control"}],"references":[{"url":"http://packetstormsecurity.com/files/162604/Dell-DBUtil_2_3.sys-IOCTL-Memory-Read-Write.html","tags":["Exploit","Third Party Advisory","VDB Entry"]},{"url":"http://packetstormsecurity.com/files/162739/DELL-dbutil_2_3.sys-2.3-Arbitrary-Write-Privilege-Escalation.html","tags":["Exploit","Third Party Advisory","VDB Entry"]},{"url":"https://www.dell.com/support/kbdoc/en-us/000186019/dsa-2021-088-dell-client-platform-security-update-for-dell-driver-insufficient-access-control-vulnerability","tags":["Mitigation","Vendor Advisory"]},{"url":"http://packetstormsecurity.com/files/162604/Dell-DBUtil_2_3.sys-IOCTL-Memory-Read-Write.html","tags":["Exploit","Third Party Advisory","VDB Entry"]},{"url":"http://packetstormsecurity.com/files/162739/DELL-dbutil_2_3.sys-2.3-Arbitrary-Write-Privilege-Escalation.html","tags":["Exploit","Third Party Advisory","VDB Entry"]},{"url":"https://www.dell.com/support/kbdoc/en-us/000186019/dsa-2021-088-dell-client-platform-security-update-for-dell-driver-insufficient-access-control-vulnerability","tags":["Mitigation","Vendor Advisory"]},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-21551","tags":["US Government Resource"]}],"techniques":[{"id":"T1068","name":"Exploitation for Privilege Escalation","tactics":["privilege-escalation"],"provenance":"ai","basis":"ai-mapping","bases":["ai-mapping"],"basisDetail":"claude-haiku-5-5: Local user exploits driver's insufficient access control","mappingType":"exploitation_technique","evidence":[{"from":"description","quote":"Local authenticated user access is required","start":171,"end":214}],"model":"claude-haiku-5-5","confidence":"medium","confidenceNote":"AI-mapped from the description (quote-validated, not expert-reviewed)"},{"id":"T1005","name":"Data from Local System","tactics":["collection"],"provenance":"ai","basis":"ai-mapping","bases":["ai-mapping"],"basisDetail":"claude-haiku-5-5: Driver can disclose information from kernel memory","mappingType":"primary_impact","evidence":[{"from":"description","quote":"may lead to escalation of privileges, denial of service, or information disclosure","start":87,"end":169}],"model":"claude-haiku-5-5","confidence":"medium","confidenceNote":"AI-mapped from the description (quote-validated, not expert-reviewed)"},{"id":"T1499.004","name":"Application or System Exploitation","tactics":["impact"],"provenance":"ai","basis":"ai-mapping","bases":["ai-mapping"],"basisDetail":"claude-haiku-5-5: Driver IOCTL can crash system, causing denial of service","mappingType":"primary_impact","evidence":[{"from":"description","quote":"may lead to escalation of privileges, denial of service","start":87,"end":142}],"model":"claude-haiku-5-5","confidence":"medium","confidenceNote":"AI-mapped from the description (quote-validated, not expert-reviewed)"}],"reports":[],"affected":[],"advisories":[],"euvd":{"id":"EUVD-2021-8823","url":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2021-8823","exploited":true,"exploitedSince":"2022-03-31","provenance":"source"},"exploits":[{"id":49893,"url":"https://www.exploit-db.com/exploits/49893","title":"DELL dbutil_2_3.sys 2.3 - Arbitrary Write to Local Privilege Escalation (LPE)","type":"local","platform":"windows","date":"2021-05-21","verified":false,"provenance":"source"}],"exploitSources":{"exploitdb":{"count":1,"earliest":"2021-05-21"},"pocGithub":{"count":11,"skipped":1,"earliest":"2021-05-13","earliestUrl":"https://github.com/waldo-irc/CVE-2021-21551","repos":[{"name":"waldo-irc/CVE-2021-21551","url":"https://github.com/waldo-irc/CVE-2021-21551","stars":258,"created":"2021-05-13"},{"name":"tijme/kernel-mii","url":"https://github.com/tijme/kernel-mii","stars":85,"created":"2022-06-25"},{"name":"mathisvickie/CVE-2021-21551","url":"https://github.com/mathisvickie/CVE-2021-21551","stars":59,"created":"2021-05-30"},{"name":"ihack4falafel/Dell-Driver-EoP-CVE-2021-21551","url":"https://github.com/ihack4falafel/Dell-Driver-EoP-CVE-2021-21551","stars":33,"created":"2021-09-03"},{"name":"nanabingies/CVE-2021-21551","url":"https://github.com/nanabingies/CVE-2021-21551","stars":26,"created":"2023-01-07"}]},"metasploit":[{"name":"Dell DBUtil_2_3.sys IOCTL 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