CVE-2026-59639
In Bouncy Castle for Java before 1.85, CMS verifySignatures returns true for SignedData with zero signers. This issue also affects Bouncy Castle for Java LTS before 2.73.12, and Bouncy Castle for Java FIPS (BC-FJA) before bcpkix-fips 1.0.12 (1.0.X series), 2.0.12 (2.0.X series) and 2.1.12 (2.1.X series).
CVSS
- Versión: 4.0
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:Amber
- Puntuación base: 8.7
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.24%
- Percentil entre todas las CVEs puntuadas: 14
- Fecha de la puntuación: 5/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
🎯 Técnicas ATT&CK
Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.
- Explotación
T1190Exploit Public-Facing Applicationinitial access75 % - Impacto principal
T1553.006Code Signing Policy Modificationdefense impairment80 % - Impacto secundario
T1565.003Runtime Data Manipulationimpact70 %
Vulnerabilidad en librería criptográfica expuesta en red (AV:N, PR:N, UI:N) que valida falsamente firmas digitales (VI:H, CWE-347). Permite bypass de verificación de integridad y autenticación de código.
Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.
🛡️ Mitigaciones ATT&CK que cubren estas técnicas
Tecnologías afectadas (3)
CWE
- CWE-347
Referencias
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-59639",
"cveTags": [],
"metrics": {
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2026-59639",
"role": "CISA Coordinator",
"options": [
{
"exploitation": "none"
},
{
"automatable": "yes"
},
{
"technicalImpact": "partial"
}
],
"version": "2.0.3",
"timestamp": "2026-08-03T13:24:06.309527Z"
}
}
],
"cvssMetricV31": [
{
"type": "Primary",
"source": "nvd@nist.gov",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 7.5,
"attackVector": "NETWORK",
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N",
"integrityImpact": "HIGH",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "NONE",
"privilegesRequired": "NONE",
"confidentialityImpact": "NONE"
},
"impactScore": 3.6,
"exploitabilityScore": 3.9
}
],
"cvssMetricV40": [
{
"type": "Secondary",
"source": "91579145-5d7b-4cc5-b925-a0262ff19630",
"cvssData": {
"Safety": "NOT_DEFINED",
"version": "4.0",
"Recovery": "NOT_DEFINED",
"baseScore": 8.7,
"Automatable": "NOT_DEFINED",
"attackVector": "NETWORK",
"baseSeverity": "HIGH",
"valueDensity": "NOT_DEFINED",
"vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:Amber",
"exploitMaturity": "NOT_DEFINED",
"providerUrgency": "AMBER",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"attackRequirements": "NONE",
"privilegesRequired": "NONE",
"subIntegrityImpact": "NONE",
"vulnIntegrityImpact": "HIGH",
"integrityRequirement": "NOT_DEFINED",
"modifiedAttackVector": "NOT_DEFINED",
"subAvailabilityImpact": "NONE",
"vulnAvailabilityImpact": "NONE",
"availabilityRequirement": "NOT_DEFINED",
"modifiedUserInteraction": "NOT_DEFINED",
"modifiedAttackComplexity": "NOT_DEFINED",
"subConfidentialityImpact": "NONE",
"vulnConfidentialityImpact": "NONE",
"confidentialityRequirement": "NOT_DEFINED",
"modifiedAttackRequirements": "NOT_DEFINED",
"modifiedPrivilegesRequired": "NOT_DEFINED",
"modifiedSubIntegrityImpact": "NOT_DEFINED",
"modifiedVulnIntegrityImpact": "NOT_DEFINED",
"vulnerabilityResponseEffort": "NOT_DEFINED",
"modifiedSubAvailabilityImpact": "NOT_DEFINED",
"modifiedVulnAvailabilityImpact": "NOT_DEFINED",
"modifiedSubConfidentialityImpact": "NOT_DEFINED",
"modifiedVulnConfidentialityImpact": "NOT_DEFINED"
}
}
]
},
"affected": [
{
"source": "91579145-5d7b-4cc5-b925-a0262ff19630",
"affectedData": [
{
"repo": "https://github.com/bcgit/bc-java",
"vendor": "Legion of the Bouncy Castle Inc.",
"modules": [
"pkix"
],
"product": "BC-JAVA",
"versions": [
{
"status": "affected",
"version": "0",
"lessThan": "1.85",
"versionType": "maven"
}
],
"platforms": [
"all"
],
"packageURL": "pkg:maven/org.bouncycastle/bcpkix-jdk18on",
"packageName": "bcpkix",
"programFiles": [
"CMSSignedData"
],
"collectionURL": "https://www.bouncycastle.org/download/bouncy-castle-java/",
"defaultStatus": "unaffected"
},
{
"repo": "https://github.com/bcgit/bc-lts-java",
"vendor": "Legion of the Bouncy Castle Inc.",
"modules": [
"pkix"
],
"product": "BC-LTS-JAVA",
"versions": [
{
"status": "affected",
"version": "2.73.0",
"lessThan": "2.73.12",
"versionType": "maven"
}
],
"platforms": [
"all"
],
"packageURL": "pkg:maven/org.bouncycastle/bcpkix-lts8on",
"packageName": "bcpkix-lts8on",
"programFiles": [
"CMSSignedData"
],
"collectionURL": "https://www.bouncycastle.org/download/bouncy-castle-java-lts/",
"defaultStatus": "unaffected"
},
{
"vendor": "Legion of the Bouncy Castle Inc.",
"product": "BC-FJA",
"versions": [
{
"status": "affected",
"version": "1.0.0",
"lessThan": "1.0.12",
"versionType": "maven"
},
{
"status": "affected",
"version": "2.0.0",
"lessThan": "2.0.12",
"versionType": "maven"
},
{
"status": "affected",
"version": "2.1.0",
"lessThan": "2.1.12",
"versionType": "maven"
}
],
"platforms": [
"all"
],
"packageURL": "pkg:maven/org.bouncycastle/bcpkix-fips",
"packageName": "bcpkix-fips",
"collectionURL": "https://www.bouncycastle.org/download/bouncy-castle-java-fips/",
"defaultStatus": "unaffected"
}
]
}
],
"published": "2026-08-03T01:16:43.700",
"references": [
{
"url": "https://github.com/bcgit/bc-java/commit/99ddc6dcc6782e6a76b0dd587c77e62eb7096ad0",
"tags": [
"Patch"
],
"source": "91579145-5d7b-4cc5-b925-a0262ff19630"
},
{
"url": "https://github.com/bcgit/bc-java/wiki/CVE%E2%80%902026%E2%80%9059639",
"tags": [
"Third Party Advisory"
],
"source": "91579145-5d7b-4cc5-b925-a0262ff19630"
}
],
"vulnStatus": "Analyzed",
"weaknesses": [
{
"type": "Secondary",
"source": "91579145-5d7b-4cc5-b925-a0262ff19630",
"description": [
{
"lang": "en",
"value": "CWE-347"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "In Bouncy Castle for Java before 1.85, CMS verifySignatures returns true for SignedData with zero signers. This issue also affects Bouncy Castle for Java LTS before 2.73.12, and Bouncy Castle for Java FIPS (BC-FJA) before bcpkix-fips 1.0.12 (1.0.X series), 2.0.12 (2.0.X series) and 2.1.12 (2.1.X series)."
}
],
"lastModified": "2026-08-28T15:33:16.413",
"configurations": [
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:a:bouncycastle:bc-java:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "FA6A5663-2E62-44AA-8A64-A3CB0DC8813B",
"versionEndExcluding": "1.85"
},
{
"criteria": "cpe:2.3:a:bouncycastle:bcpkix-fips:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "C878934F-879A-4F9A-B81C-C284BF7797D4",
"versionEndExcluding": "1.0.12"
},
{
"criteria": "cpe:2.3:a:bouncycastle:bcpkix-fips:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "D0FF4FC3-75CF-4C5C-AEF1-342B8123264B",
"versionEndExcluding": "2.0.12",
"versionStartIncluding": "2.0.7"
},
{
"criteria": "cpe:2.3:a:bouncycastle:bcpkix-fips:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "A5C3EAC6-7756-48AC-9129-A9BE7E11A8C7",
"versionEndExcluding": "2.1.12",
"versionStartIncluding": "2.1.8"
},
{
"criteria": "cpe:2.3:a:bouncycastle:bouncy_castle_for_java_lts:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "F5ED4F42-08FF-4642-815D-1ED0C82FDBD2",
"versionEndIncluding": "2.73.11"
}
],
"operator": "OR"
}
]
}
],
"sourceIdentifier": "91579145-5d7b-4cc5-b925-a0262ff19630"
}