[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"$fdXzs1M_Yz-MI2G9kKtDlLDA2zcqBsE-1nQ5Jv0zZWOE":3,"g5a-risk:CVE-2020-29487":110},{"success":4,"data":5,"meta":108},true,{"cveId":6,"title":7,"description":8,"shortDescription":9,"publishedDate":10,"lastModified":11,"cvssScore":12,"cvssVector":13,"cvssMetrics":14,"epssScore":38,"epssPercentile":26,"epssTimeSeries":39,"severity":40,"affectedProducts":41,"affectedProductsCount":47,"references":48,"referencesCount":60,"weaknesses":61,"weaknessesCount":47,"isActivelyExploited":70,"cisaInfo":26,"otxData":26,"relatedBlogPosts":71,"seoMetadata":72,"configurations":97,"relatedVendorCves":106,"notableEvents":107},"CVE-2020-29487","What is CVE-2020-29487?","An issue was discovered in Xen XAPI before 2020-12-15. Certain xenstore keys provide feedback from the guest, and are therefore watched by toolstack. Specifically, keys are watched by xenopsd, and data are forwarded via RPC through message-switch to xapi. The watching logic in xenopsd sends one RPC update containing all data, any time any single xenstore key is updated, and therefore has O(N^2) time complexity. Furthermore, message-switch retains recent (currently 128) RPC messages for diagnostic purposes, yielding O(M*N) space complexity. The quantity of memory a single guest can monopolise is bounded by xenstored quota, but the quota is fairly large. It is believed to be in excess of 1G per malicious guest. In practice, this manifests as a host denial of service, either through message-switch thrashing against swap, or OOMing entirely, depending on dom0's configuration. (There are no quotas in xenopsd to limit the quantity of keys that result in RPC traffic.) A buggy or malicious guest can cause unreasonable memory usage in dom0, resulting in a host denial of service. All versions of XAPI are vulnerable. Systems that are not using the XAPI toolstack are not vulnerable.","An issue was discovered in Xen XAPI before 2020-12-15. Certain xenstore keys provide feedback from the guest, and are therefore watched by toolstack. Specifi...","2020-12-15T18:15:15.663","2021-12-10T02:12:08.497",7.5,"CVSS:3.1\u002FAV:N\u002FAC:L\u002FPR:N\u002FUI:N\u002FS:U\u002FC:N\u002FI:N\u002FA:H",{"CVSSMetricV31":15,"CVSSMetricV30":26,"CVSSMetricV2":29,"CVSSMetricV40":26},[16],{"Source":17,"Type":18,"CVSSData":19,"ExploitabilityScore":27,"ImpactScore":28},"nvd@nist.gov","Primary",{"Version":20,"VectorString":13,"AttackVector":21,"AttackComplexity":22,"PrivilegesRequired":23,"UserInteraction":23,"Scope":24,"ConfidentialityImpact":23,"IntegrityImpact":23,"AvailabilityImpact":25,"BaseScore":12,"BaseSeverity":25,"ExploitCodeMaturity":26,"RemediationLevel":26,"ReportConfidence":26,"TemporalScore":26,"TemporalSeverity":26,"ConfidentialityRequirement":26,"IntegrityRequirement":26,"AvailabilityRequirement":25,"ModifiedAttackVector":26,"ModifiedAttackComplexity":26,"ModifiedPrivilegesRequired":26,"ModifiedUserInteraction":26,"ModifiedScope":26,"ModifiedConfidentialityImpact":26,"ModifiedIntegrityImpact":26,"ModifiedAvailabilityImpact":26,"EnvironmentalScore":26,"EnvironmentalSeverity":26},"3.1","NETWORK","LOW","NONE","UNCHANGED","HIGH",null,3.9,3.6,[30],{"Source":17,"Type":18,"CVSSData":31,"BaseSeverity":25,"ExploitabilityScore":36,"ImpactScore":37,"ACInsufInfo":26,"ObtainAllPrivilege":26,"ObtainUserPrivilege":26,"ObtainOtherPrivilege":26,"UserInteractionRequired":26},{"Version":32,"VectorString":33,"AccessVector":21,"AccessComplexity":22,"Authentication":23,"ConfidentialityImpact":23,"IntegrityImpact":23,"AvailabilityImpact":34,"BaseScore":35,"BaseSeverity":26,"Exploitability":26,"RemediationLevel":26,"ReportConfidence":26,"TemporalScore":26,"CollateralDamagePotential":26,"TargetDistribution":26,"ConfidentialityRequirement":26,"IntegrityRequirement":26,"AvailabilityRequirement":26,"EnvironmentalScore":26},"2.0","AV:N\u002FAC:L\u002FAu:N\u002FC:N\u002FI:N\u002FA:C","COMPLETE",7.8,10,6.9,0.01446,[38,38,38,38,38,38,38],"High",[42],{"vendor":43,"product":44,"version":45,"criteria":46,"vulnerable":4},"xen","xapi","*","cpe:2.3:o:xen:xapi:*:*:*:*:*:*:*:*",1,[49,54],{"url":50,"source":51,"tags":52},"https:\u002F\u002Fsecurity.gentoo.org\u002Fglsa\u002F202107-30","Gentoo",[53],"Third Party Advisory",{"url":55,"source":56,"tags":57},"https:\u002F\u002Fxenbits.xenproject.org\u002Fxsa\u002Fadvisory-354.html","Xenproject",[58,59],"Patch","Vendor Advisory",2,[62],{"id":63,"name":64,"description":65,"extendedDescription":66,"status":67,"abstraction":68,"structure":69},"CWE-770","Allocation of Resources Without Limits or Throttling","The product allocates a reusable resource or group of resources on behalf of an actor without imposing any restrictions on the size or number of resources that can be allocated, in violation of the intended security policy for that actor.","Code frequently has to work with limited resources, so programmers must be careful to ensure that resources are not consumed too quickly, or too easily.  Without use of quotas, resource limits, or other protection mechanisms, it can be easy for an attacker to consume many resources by rapidly making many requests, or causing larger resources to be used than is needed. When too many resources are allocated, or if a single resource is too large, then it can prevent the code from working correctly, possibly leading to a denial of service.","Incomplete","Base","Simple",false,[],{"title":73,"metaDescription":74,"keywords":75,"canonicalUrl":76,"structuredData":77},"What is CVE-2020-29487? Vulnerability Analysis | Security Advisory | Precursor Intelligence","Comprehensive analysis of CVE-2020-29487, a high severity cyber security vulnerability from 2020. An issue was discovered in Xen XAPI before 2020-12-15. Cert...","CVE-2020-29487, CVE-2020-29487 vulnerability, CVE-2020-29487 security, high severity vulnerability, cybersecurity, vulnerability analysis, security advisory, CVE database, threat intelligence, security research, vulnerability assessment, cyber threats, 2020, CVSS score, exploit, patch, remediation, xen security, xapi vulnerability","\u002Fwhat-is\u002Fcve-2020-29487",{"@context":78,"@type":79,"headline":73,"description":74,"datePublished":10,"dateModified":11,"author":80,"publisher":84,"about":88,"mainEntityOfPage":92,"articleSection":95,"keywords":96},"https:\u002F\u002Fschema.org","TechArticle",{"@type":81,"name":82,"url":83},"Organization","Precursor Intelligence","https:\u002F\u002Fprecursorintelligence.com",{"@type":81,"name":82,"url":83,"logo":85},{"@type":86,"url":87},"ImageObject","https:\u002F\u002Fprecursorintelligence.com\u002Fimg\u002Flogos\u002Feplogo.png",{"@type":89,"name":6,"description":90,"additionalType":91},"Thing","Cybersecurity Vulnerability","https:\u002F\u002Fschema.org\u002FSoftwareBug",{"@type":93,"@id":94},"WebPage","https:\u002F\u002Fprecursorintelligence.com\u002Fwhat-is\u002Fcve-2020-29487","Cybersecurity","CVE-2020-29487, CVE-2020-29487 vulnerability, CVE-2020-29487 security, high severity vulnerability, cybersecurity, vulnerability analysis, security advisory, CVE database, threat intelligence, security research",[98],{"Operator":26,"Negate":26,"Nodes":99},[100],{"Operator":101,"Negate":26,"CPEMatch":102},"OR",[103],{"Vulnerable":4,"Criteria":46,"MatchCriteriaID":104,"VersionStartExcluding":26,"VersionStartIncluding":26,"VersionEndExcluding":105,"VersionEndIncluding":26},"E60C15D4-5A84-4767-A567-E02FEBCB60EC","2020-12-15",[],[],{"lastModified":11,"cacheTime":109,"version":32},1792249098758,{"score":111,"band":112,"action":113,"scoredAt":114},47,"Medium","Plan remediation","2026-10-16T06:50:06.711144+00:00"]