[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"$fc3wfbca9cO99xPCNp9GBhidZfZ_WePhj5--VfnS57AQ":3,"g5a-risk:CVE-2021-3493":189},{"success":4,"data":5,"meta":187},true,{"cveId":6,"title":7,"description":8,"shortDescription":9,"publishedDate":10,"lastModified":11,"cvssScore":12,"cvssVector":13,"cvssMetrics":14,"epssScore":50,"epssPercentile":28,"epssTimeSeries":51,"severity":52,"affectedProducts":53,"affectedProductsCount":59,"references":60,"referencesCount":107,"weaknesses":108,"weaknessesCount":29,"isActivelyExploited":4,"cisaInfo":123,"otxData":28,"relatedBlogPosts":124,"seoMetadata":125,"configurations":150,"relatedVendorCves":171,"notableEvents":172},"CVE-2021-3493","What is CVE-2021-3493?","The overlayfs implementation in the linux kernel did not properly validate with respect to user namespaces the setting of file capabilities on files in an underlying file system. Due to the combination of unprivileged user namespaces along with a patch carried in the Ubuntu kernel to allow unprivileged overlay mounts, an attacker could use this to gain elevated privileges.","The overlayfs implementation in the linux kernel did not properly validate with respect to user namespaces the setting of file capabilities on files in an 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Party Advisory","VDB Entry",{"url":69,"source":63,"tags":70},"http:\u002F\u002Fpacketstormsecurity.com\u002Ffiles\u002F162866\u002FUbuntu-OverlayFS-Local-Privilege-Escalation.html",[66,67,71],"Press\u002FMedia Coverage",{"url":73,"source":63,"tags":74},"http:\u002F\u002Fpacketstormsecurity.com\u002Ffiles\u002F165151\u002FUbuntu-Overlayfs-Local-Privilege-Escalation.html",[65,66,67],{"url":76,"source":77,"tags":78},"https:\u002F\u002Fgit.kernel.org\u002Fpub\u002Fscm\u002Flinux\u002Fkernel\u002Fgit\u002Ftorvalds\u002Flinux.git\u002Fcommit\u002F?id=7c03e2cda4a584cadc398e8f6641ca9988a39d52","Kernel",[79,80,66],"Mailing List","Patch",{"url":82,"source":83,"tags":84},"https:\u002F\u002Fubuntu.com\u002Fsecurity\u002Fnotices\u002FUSN-4917-1","Ubuntu",[85],"Vendor Advisory",{"url":87,"source":88,"tags":89},"https:\u002F\u002Fwww.openwall.com\u002Flists\u002Foss-security\u002F2021\u002F04\u002F16\u002F1","Openwall",[79,66],{"url":62,"source":63,"tags":91},[65,66,67],{"url":69,"source":63,"tags":93},[66,67,71],{"url":73,"source":63,"tags":95},[65,66,67],{"url":76,"source":77,"tags":97},[79,80,66],{"url":82,"source":83,"tags":99},[85],{"url":87,"source":88,"tags":101},[79,66],{"url":103,"source":104,"tags":105},"https:\u002F\u002Fwww.cisa.gov\u002Fknown-exploited-vulnerabilities-catalog?field_cve=CVE-2021-3493","CISA",[106],"US Government Resource",13,[109,116],{"id":110,"name":111,"description":112,"extendedDescription":46,"status":113,"abstraction":114,"structure":115},"CWE-270","Privilege Context Switching Error","The product does not properly manage privileges while it is switching between different contexts that have different privileges or spheres of control.","Draft","Base","Simple",{"id":117,"name":118,"description":119,"extendedDescription":120,"status":121,"abstraction":122,"structure":115},"CWE-863","Incorrect Authorization","The product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check. This allows attackers to bypass intended access restrictions.","Assuming a user with a given identity, authorization is the process of determining whether that user can access a given resource, based on the user's privileges and any permissions or other access-control specifications that apply to the resource.\nWhen access control checks are incorrectly applied, users are able to access data or perform actions that they should not be allowed to perform. This can lead to a wide range of problems, including information exposures, denial of service, and arbitrary code execution.","Incomplete","Class",{"shortDescription":46,"requiredAction":46,"vulnerabilityName":46,"dateAdded":28},[],{"title":126,"metaDescription":127,"keywords":128,"canonicalUrl":129,"structuredData":130},"What is CVE-2021-3493? Vulnerability Analysis | Security Advisory | EdgeProtect","Comprehensive analysis of CVE-2021-3493, a high severity cyber security vulnerability from 2021. High exploit probability (49.2%). The overlayfs implementati...","CVE-2021-3493, CVE-2021-3493 vulnerability, CVE-2021-3493 security, high severity vulnerability, cybersecurity, vulnerability analysis, security advisory, CVE database, threat intelligence, security research, vulnerability assessment, cyber threats, 2021, CVSS score, exploit, patch, remediation, canonical security, ubuntu_linux vulnerability, high risk vulnerability, actively exploited, exploit available","\u002Fwhat-is\u002Fcve-2021-3493",{"@context":131,"@type":132,"headline":126,"description":127,"datePublished":10,"dateModified":11,"author":133,"publisher":137,"about":141,"mainEntityOfPage":145,"articleSection":148,"keywords":149},"https:\u002F\u002Fschema.org","TechArticle",{"@type":134,"name":135,"url":136},"Organization","EdgeProtect","https:\u002F\u002Fedgeprotect.io",{"@type":134,"name":135,"url":136,"logo":138},{"@type":139,"url":140},"ImageObject","https:\u002F\u002Fedgeprotect.io\u002Fimg\u002Flogos\u002Fedgeprotect-logo-512.png",{"@type":142,"name":6,"description":143,"additionalType":144},"Thing","Cybersecurity Vulnerability","https:\u002F\u002Fschema.org\u002FSoftwareBug",{"@type":146,"@id":147},"WebPage","https:\u002F\u002Fedgeprotect.io\u002Fwhat-is\u002Fcve-2021-3493","Cybersecurity","CVE-2021-3493, CVE-2021-3493 vulnerability, CVE-2021-3493 security, high severity vulnerability, cybersecurity, vulnerability analysis, security advisory, CVE database, threat intelligence, security research",[151,163],{"Operator":28,"Negate":28,"Nodes":152},[153],{"Operator":154,"Negate":49,"CPEMatch":155},"OR",[156,159],{"Vulnerable":4,"Criteria":58,"MatchCriteriaID":157,"VersionStartExcluding":28,"VersionStartIncluding":28,"VersionEndExcluding":158,"VersionEndIncluding":28},"90A80DE7-3EFA-464C-9D31-C46521FFBFBF","18.04",{"Vulnerable":4,"Criteria":58,"MatchCriteriaID":160,"VersionStartExcluding":28,"VersionStartIncluding":161,"VersionEndExcluding":162,"VersionEndIncluding":28},"2027773B-26DA-408E-B71D-40D05690D9EA","18.04.1","20.04",{"Operator":28,"Negate":28,"Nodes":164},[165],{"Operator":154,"Negate":49,"CPEMatch":166},[167],{"Vulnerable":4,"Criteria":168,"MatchCriteriaID":169,"VersionStartExcluding":28,"VersionStartIncluding":28,"VersionEndExcluding":170,"VersionEndIncluding":28},"cpe:2.3:o:canonical:ubuntu_linux:*:*:*:*:-:*:*:*","ACAB2EE0-EC21-4669-840F-94F6C3028C64","20.10",[],[173,180],{"id":174,"eventType":175,"eventTime":176,"details":177,"label":178,"color":179},"e4f80966-9d65-408b-ac42-b3bdf4f3dd05","HIGH_EPSS_DELTA","2025-11-19T04:05:58.718078+00:00","Daily EPSS score increased by 0.132 on 2023-12-30","EPSS Score Increased","red",{"id":181,"eventType":182,"eventTime":183,"details":184,"label":185,"color":186},"8796d947-ccfe-4309-805e-61dffecdf9d6","LOW_EPSS_DELTA","2025-11-22T04:05:47.086091+00:00","Daily EPSS score decreased by 0.167 on 2023-12-30","EPSS Score Decreased","green",{"lastModified":11,"cacheTime":188,"version":42},1793200409124,{"score":190,"band":52,"action":191,"scoredAt":192},72,"Emergency patch","2026-10-28T06:50:45.10191+00:00"]