[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"$fQfS-OlaYZBXTyHBIqeodecvh1AFHhZTskeQMTFqgeRM":3,"g5a-risk:CVE-2023-4421":111},{"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":32,"epssPercentile":27,"epssTimeSeries":33,"severity":34,"affectedProducts":35,"affectedProductsCount":41,"references":42,"referencesCount":60,"weaknesses":61,"weaknessesCount":41,"isActivelyExploited":70,"cisaInfo":27,"otxData":27,"relatedBlogPosts":71,"seoMetadata":72,"configurations":97,"relatedVendorCves":106,"notableEvents":107},"CVE-2023-4421","What is CVE-2023-4421?","The NSS code used for checking PKCS#1 v1.5 was leaking information useful in mounting Bleichenbacher-like attacks. Both the overall correctness of the padding as well as the length of the encrypted message was leaking through timing side-channel. By sending large number of attacker-selected ciphertexts, the attacker would be able to decrypt a previously intercepted PKCS#1 v1.5 ciphertext (for example, to decrypt a TLS session that used RSA key exchange), or forge a signature using the victim's key. The issue was fixed by implementing the implicit rejection algorithm, in which the NSS returns a deterministic random message in case invalid padding is detected, as proposed in the Marvin Attack paper. This vulnerability affects NSS \u003C 3.61.","The NSS code used for checking PKCS#1 v1.5 was leaking information useful in mounting Bleichenbacher-like attacks. Both the overall correctness of the paddin...","2023-12-12T17:15:08.347","2025-11-04T20:17:10.927",6.5,"CVSS:3.1\u002FAV:N\u002FAC:L\u002FPR:L\u002FUI:N\u002FS:U\u002FC:H\u002FI:N\u002FA:N",{"CVSSMetricV31":15,"CVSSMetricV30":30,"CVSSMetricV2":31,"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":22,"UserInteraction":23,"Scope":24,"ConfidentialityImpact":25,"IntegrityImpact":23,"AvailabilityImpact":23,"BaseScore":12,"BaseSeverity":26,"ExploitCodeMaturity":27,"RemediationLevel":27,"ReportConfidence":27,"TemporalScore":27,"TemporalSeverity":27,"ConfidentialityRequirement":27,"IntegrityRequirement":27,"AvailabilityRequirement":27,"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","MEDIUM",null,2.8,3.6,[],[],0.00762,[32,32,32,32,32,32,32],"Medium",[36],{"vendor":37,"product":38,"version":39,"criteria":40,"vulnerable":4},"mozilla","nss","*","cpe:2.3:a:mozilla:nss:*:*:*:*:*:*:*:*",1,[43,48,52,54,58],{"url":44,"source":45,"tags":46},"https:\u002F\u002Fbugzilla.mozilla.org\u002Fshow_bug.cgi?id=1651411","Mozilla",[47],"Issue Tracking",{"url":49,"source":45,"tags":50},"https:\u002F\u002Fwww.mozilla.org\u002Fsecurity\u002Fadvisories\u002Fmfsa2023-53\u002F",[47,51],"Vendor Advisory",{"url":44,"source":45,"tags":53},[47],{"url":55,"source":56,"tags":57},"https:\u002F\u002Flists.debian.org\u002Fdebian-lts-announce\u002F2023\u002F10\u002Fmsg00039.html","Debian",[],{"url":49,"source":45,"tags":59},[47,51],5,[62],{"id":63,"name":64,"description":65,"extendedDescription":66,"status":67,"abstraction":68,"structure":69},"CWE-203","Observable Discrepancy","The product behaves differently or sends different responses under different circumstances in a way that is observable to an unauthorized actor, which exposes security-relevant information about the state of the product, such as whether a particular operation was successful or not.","Discrepancies can take many forms, and variations may be detectable in timing, control flow, communications such as replies or requests, or general behavior. These discrepancies can reveal information about the product's operation or internal state to an unauthorized actor. In some cases, discrepancies can be used by attackers to form a side channel.","Incomplete","Base","Simple",false,[],{"title":73,"metaDescription":74,"keywords":75,"canonicalUrl":76,"structuredData":77},"What is CVE-2023-4421? Vulnerability Analysis | Security Advisory | Precursor Intelligence","Comprehensive analysis of CVE-2023-4421, a medium severity cyber security vulnerability from 2023. The NSS code used for checking PKCS#1 v1.5 was leaking inf...","CVE-2023-4421, CVE-2023-4421 vulnerability, CVE-2023-4421 security, medium severity vulnerability, cybersecurity, vulnerability analysis, security advisory, CVE database, threat intelligence, security research, vulnerability assessment, cyber threats, 2023, CVSS score, exploit, patch, remediation, mozilla security, nss vulnerability","\u002Fwhat-is\u002Fcve-2023-4421",{"@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-2023-4421","Cybersecurity","CVE-2023-4421, CVE-2023-4421 vulnerability, CVE-2023-4421 security, medium severity vulnerability, cybersecurity, vulnerability analysis, security advisory, CVE database, threat intelligence, security research",[98],{"Operator":27,"Negate":27,"Nodes":99},[100],{"Operator":101,"Negate":70,"CPEMatch":102},"OR",[103],{"Vulnerable":4,"Criteria":40,"MatchCriteriaID":104,"VersionStartExcluding":27,"VersionStartIncluding":27,"VersionEndExcluding":105,"VersionEndIncluding":27},"885547E8-A55A-4B53-A0A6-FDA8745A5D0D","3.6.1",[],[],{"lastModified":11,"cacheTime":109,"version":110},1792353407936,"2.0",{"score":112,"band":113,"action":114,"scoredAt":115},30,"Low","Monitor","2026-10-16T07:00:05.410067+00:00"]