[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"$ftOp2rC9RfAV5w1l69BTR99qGx3bN79w40oKkz7mP9r0":3,"g5a-risk:CVE-2021-33913":134},{"success":4,"data":5,"meta":132},true,{"cveId":6,"title":7,"description":8,"shortDescription":9,"publishedDate":10,"lastModified":11,"cvssScore":12,"cvssVector":13,"cvssMetrics":14,"epssScore":40,"epssPercentile":27,"epssTimeSeries":41,"severity":42,"affectedProducts":43,"affectedProductsCount":49,"references":50,"referencesCount":70,"weaknesses":71,"weaknessesCount":49,"isActivelyExploited":80,"cisaInfo":27,"otxData":27,"relatedBlogPosts":81,"seoMetadata":82,"configurations":107,"relatedVendorCves":116,"notableEvents":117},"CVE-2021-33913","What is CVE-2021-33913?","libspf2 before 1.2.11 has a heap-based buffer overflow that might allow remote attackers to execute arbitrary code (via an unauthenticated e-mail message from anywhere on the Internet) with a crafted SPF DNS record, because of SPF_record_expand_data in spf_expand.c. The amount of overflowed data depends on the relationship between the length of an entire domain name and the length of its leftmost label. The vulnerable code may be part of the supply chain of a site's e-mail infrastructure (e.g., with additional configuration, Exim can use libspf2; the Postfix web site links to unofficial patches for use of libspf2 with Postfix; older versions of spfquery relied on libspf2) but most often is not.","libspf2 before 1.2.11 has a heap-based buffer overflow that might allow remote attackers to execute arbitrary code (via an unauthenticated e-mail message fro...","2022-01-19T18:15:07.83","2024-01-15T17:15:08.263",9.8,"CVSS:3.1\u002FAV:N\u002FAC:L\u002FPR:N\u002FUI:N\u002FS:U\u002FC:H\u002FI:H\u002FA:H",{"CVSSMetricV31":15,"CVSSMetricV30":27,"CVSSMetricV2":30,"CVSSMetricV40":27},[16],{"Source":17,"Type":18,"CVSSData":19,"ExploitabilityScore":28,"ImpactScore":29},"nvd@nist.gov","Primary",{"Version":20,"VectorString":13,"AttackVector":21,"AttackComplexity":22,"PrivilegesRequired":23,"UserInteraction":23,"Scope":24,"ConfidentialityImpact":25,"IntegrityImpact":25,"AvailabilityImpact":25,"BaseScore":12,"BaseSeverity":26,"ExploitCodeMaturity":27,"RemediationLevel":27,"ReportConfidence":27,"TemporalScore":27,"TemporalSeverity":27,"ConfidentialityRequirement":27,"IntegrityRequirement":27,"AvailabilityRequirement":25,"ModifiedAttackVector":27,"ModifiedAttackComplexity":27,"ModifiedPrivilegesRequired":27,"ModifiedUserInteraction":27,"ModifiedScope":27,"ModifiedConfidentialityImpact":27,"ModifiedIntegrityImpact":27,"ModifiedAvailabilityImpact":27,"EnvironmentalScore":27,"EnvironmentalSeverity":27},"3.1","NETWORK","LOW","NONE","UNCHANGED","HIGH","CRITICAL",null,3.9,5.9,[31],{"Source":17,"Type":18,"CVSSData":32,"BaseSeverity":25,"ExploitabilityScore":38,"ImpactScore":39,"ACInsufInfo":27,"ObtainAllPrivilege":27,"ObtainUserPrivilege":27,"ObtainOtherPrivilege":27,"UserInteractionRequired":27},{"Version":33,"VectorString":34,"AccessVector":21,"AccessComplexity":35,"Authentication":23,"ConfidentialityImpact":36,"IntegrityImpact":36,"AvailabilityImpact":36,"BaseScore":37,"BaseSeverity":27,"Exploitability":27,"RemediationLevel":27,"ReportConfidence":27,"TemporalScore":27,"CollateralDamagePotential":27,"TargetDistribution":27,"ConfidentialityRequirement":27,"IntegrityRequirement":27,"AvailabilityRequirement":27,"EnvironmentalScore":27},"2.0","AV:N\u002FAC:M\u002FAu:N\u002FC:C\u002FI:C\u002FA:C","MEDIUM","COMPLETE",9.3,8.6,10,0.09643,[40,40,40,40,40,40,40],"Critical",[44],{"vendor":45,"product":46,"version":47,"criteria":48,"vulnerable":4},"libspf2_project","libspf2","*","cpe:2.3:a:libspf2_project:libspf2:*:*:*:*:*:*:*:*",1,[51,56,61,66],{"url":52,"source":53,"tags":54},"https:\u002F\u002Fgithub.com\u002Fshevek\u002Flibspf2\u002Ftree\u002F8131fe140704eaae695e76b5cd09e39bd1dd220b","GitHub",[55],"Third Party Advisory",{"url":57,"source":58,"tags":59},"https:\u002F\u002Flists.debian.org\u002Fdebian-lts-announce\u002F2022\u002F01\u002Fmsg00015.html","Debian",[60,55],"Mailing List",{"url":62,"source":63,"tags":64},"https:\u002F\u002Fnathanielbennett.com\u002Fblog\u002Flibspf2-cve-jan-2022-disclosure","Nathanielbennett",[65,55],"Exploit",{"url":67,"source":68,"tags":69},"https:\u002F\u002Fsecurity.gentoo.org\u002Fglsa\u002F202401-22","Gentoo",[],4,[72],{"id":73,"name":74,"description":75,"extendedDescription":76,"status":77,"abstraction":78,"structure":79},"CWE-787","Out-of-bounds Write","The product writes data past the end, or before the beginning, of the intended buffer.","","Draft","Base","Simple",false,[],{"title":83,"metaDescription":84,"keywords":85,"canonicalUrl":86,"structuredData":87},"What is CVE-2021-33913? Vulnerability Analysis | Security Advisory | EdgeProtect","Comprehensive analysis of CVE-2021-33913, a critical severity cyber security vulnerability from 2022. libspf2 before 1.2.11 has a heap-based buffer overflow ...","CVE-2021-33913, CVE-2021-33913 vulnerability, CVE-2021-33913 security, critical severity vulnerability, cybersecurity, vulnerability analysis, security advisory, CVE database, threat intelligence, security research, vulnerability assessment, cyber threats, 2022, CVSS score, exploit, patch, remediation, libspf2_project security, libspf2 vulnerability","\u002Fwhat-is\u002Fcve-2021-33913",{"@context":88,"@type":89,"headline":83,"description":84,"datePublished":10,"dateModified":11,"author":90,"publisher":94,"about":98,"mainEntityOfPage":102,"articleSection":105,"keywords":106},"https:\u002F\u002Fschema.org","TechArticle",{"@type":91,"name":92,"url":93},"Organization","EdgeProtect","https:\u002F\u002Fedgeprotect.io",{"@type":91,"name":92,"url":93,"logo":95},{"@type":96,"url":97},"ImageObject","https:\u002F\u002Fedgeprotect.io\u002Fimg\u002Flogos\u002Fedgeprotect-logo-512.png",{"@type":99,"name":6,"description":100,"additionalType":101},"Thing","Cybersecurity Vulnerability","https:\u002F\u002Fschema.org\u002FSoftwareBug",{"@type":103,"@id":104},"WebPage","https:\u002F\u002Fedgeprotect.io\u002Fwhat-is\u002Fcve-2021-33913","Cybersecurity","CVE-2021-33913, CVE-2021-33913 vulnerability, CVE-2021-33913 security, critical severity vulnerability, cybersecurity, vulnerability analysis, security advisory, CVE database, threat intelligence, security research",[108],{"Operator":27,"Negate":27,"Nodes":109},[110],{"Operator":111,"Negate":27,"CPEMatch":112},"OR",[113],{"Vulnerable":4,"Criteria":48,"MatchCriteriaID":114,"VersionStartExcluding":27,"VersionStartIncluding":27,"VersionEndExcluding":115,"VersionEndIncluding":27},"B9926529-9106-4A0B-85FA-F1E286816711","1.2.11",[],[118,125],{"id":119,"eventType":120,"eventTime":121,"details":122,"label":123,"color":124},"37f4ecf9-d9d9-460c-8f34-dd7ee729c9fb","HIGH_EPSS_DELTA","2025-11-19T04:05:59.471238+00:00","Daily EPSS score increased by 0.128 on 2023-12-30","EPSS Score Increased","red",{"id":126,"eventType":127,"eventTime":128,"details":129,"label":130,"color":131},"45e66c7d-a8cc-47f1-adbf-82e35a461ef3","LOW_EPSS_DELTA","2025-11-22T04:05:47.734871+00:00","Daily EPSS score decreased by 0.128 on 2023-12-30","EPSS Score Decreased","green",{"lastModified":11,"cacheTime":133,"version":33},1793244649322,{"score":135,"band":136,"action":137,"scoredAt":138},62,"Medium","Plan remediation","2026-07-01T10:27:32.861058+00:00"]