CVE-2026-82078
An unsafe dynamic class loading vulnerability exists in the database connection utilities of PaperCut MF and PaperCut NG. The application instantiates database driver classes based on configurable driver names without validating against an allowlist of approved drivers. If an attacker can manipulate system configuration parameters, this enables the execution of arbitrary Java bytecode residing on the application classpath under the security context of the PaperCut server process.
CVSS
- Versión: 4.0
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/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:X
- Puntuación base: 9.4
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 61%
- Percentil entre todas las CVEs puntuadas: 99
- Fecha de la puntuación: 6/10/2026
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).
CISA KEV — explotada activamente
- Añadida al catálogo: 31/8/2026
- Plazo de remediación: 14/9/2026
- Uso conocido en ransomware: Unknown
🎯 Técnicas ATT&CK
Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.
- Explotación
T1210Exploitation of Remote Serviceslateral movement85 % - Impacto principal
T1059.004Unix Shellexecution90 % - Impacto secundario
T1005Data from Local Systemcollection70 %
AV:N, PR:H sin UI permite explotar servicios remotos. Carga dinámica de clases Java sin validación ejecuta bytecode arbitrario (T1059.004) bajo contexto de proceso del servidor PaperCut, con potencial escalada de privilegios (T1548.004) y acceso a datos de configuración (T1005).
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 (2)
CWE
- CWE-470
Referencias
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-82078",
"cveTags": [],
"metrics": {
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2026-82078",
"role": "CISA Coordinator",
"options": [
{
"exploitation": "active"
},
{
"automatable": "no"
},
{
"technicalImpact": "total"
}
],
"version": "2.0.3",
"timestamp": "2026-08-28T00:00:00+00:00"
}
}
],
"cvssMetricV31": [
{
"type": "Primary",
"source": "nvd@nist.gov",
"cvssData": {
"scope": "CHANGED",
"version": "3.1",
"baseScore": 9.1,
"attackVector": "NETWORK",
"baseSeverity": "CRITICAL",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H",
"integrityImpact": "HIGH",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "HIGH",
"confidentialityImpact": "HIGH"
},
"impactScore": 6,
"exploitabilityScore": 2.3
}
],
"cvssMetricV40": [
{
"type": "Secondary",
"source": "eb41dac7-0af8-4f84-9f6d-0272772514f4",
"cvssData": {
"Safety": "NOT_DEFINED",
"version": "4.0",
"Recovery": "NOT_DEFINED",
"baseScore": 9.4,
"Automatable": "NOT_DEFINED",
"attackVector": "NETWORK",
"baseSeverity": "CRITICAL",
"valueDensity": "NOT_DEFINED",
"vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/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:X",
"exploitMaturity": "NOT_DEFINED",
"providerUrgency": "NOT_DEFINED",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"attackRequirements": "NONE",
"privilegesRequired": "HIGH",
"subIntegrityImpact": "HIGH",
"vulnIntegrityImpact": "HIGH",
"integrityRequirement": "NOT_DEFINED",
"modifiedAttackVector": "NOT_DEFINED",
"subAvailabilityImpact": "HIGH",
"vulnAvailabilityImpact": "HIGH",
"availabilityRequirement": "NOT_DEFINED",
"modifiedUserInteraction": "NOT_DEFINED",
"modifiedAttackComplexity": "NOT_DEFINED",
"subConfidentialityImpact": "HIGH",
"vulnConfidentialityImpact": "HIGH",
"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": "eb41dac7-0af8-4f84-9f6d-0272772514f4",
"affectedData": [
{
"vendor": "PaperCut",
"product": "PaperCut MF/NG",
"versions": [
{
"status": "affected",
"version": "0",
"lessThan": "24.1.10",
"versionType": "semver"
},
{
"status": "affected",
"version": "25.0.0",
"lessThan": "25.0.13",
"versionType": "semver"
},
{
"status": "affected",
"version": "26.0.0",
"lessThan": "26.0.5",
"versionType": "semver"
}
],
"defaultStatus": "unaffected"
}
]
}
],
"published": "2026-08-28T16:18:31.240",
"references": [
{
"url": "https://www.papercut.com/kb/Main/security-bulletin-27-aug-2026-urgent-security-advisory/",
"tags": [
"Patch",
"Vendor Advisory"
],
"source": "eb41dac7-0af8-4f84-9f6d-0272772514f4"
},
{
"url": "https://github.com/rapid7/metasploit-framework/pull/21842",
"tags": [
"Issue Tracking",
"Patch"
],
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"
},
{
"url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-82078",
"tags": [
"Patch",
"Third Party Advisory",
"US Government Resource"
],
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"
}
],
"vulnStatus": "Analyzed",
"weaknesses": [
{
"type": "Secondary",
"source": "eb41dac7-0af8-4f84-9f6d-0272772514f4",
"description": [
{
"lang": "en",
"value": "CWE-470"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "An unsafe dynamic class loading vulnerability exists in the database connection utilities of PaperCut MF and PaperCut NG. The application instantiates database driver classes based on configurable driver names without validating against an allowlist of approved drivers. If an attacker can manipulate system configuration parameters, this enables the execution of arbitrary Java bytecode residing on the application classpath under the security context of the PaperCut server process."
}
],
"lastModified": "2026-09-14T00:16:56.777",
"cisaActionDue": "2026-09-14",
"cisaExploitAdd": "2026-08-31",
"configurations": [
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:a:papercut:papercut_mf:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "F2AF3AB4-FD10-4DE1-B906-011F45948BD0",
"versionEndExcluding": "24.1.9"
},
{
"criteria": "cpe:2.3:a:papercut:papercut_mf:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "8F6ED0B8-62DC-4CF9-9810-2CCB824FBCA8",
"versionEndExcluding": "25.0.12",
"versionStartIncluding": "25.0.2"
},
{
"criteria": "cpe:2.3:a:papercut:papercut_mf:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "51E91B81-E311-4BB9-A753-671F0C59E7F7",
"versionEndExcluding": "26.0.4",
"versionStartIncluding": "26.0.2"
},
{
"criteria": "cpe:2.3:a:papercut:papercut_ng:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "44FCDCDE-4126-4F4F-89FC-D44924F45C82",
"versionEndExcluding": "24.1.9"
},
{
"criteria": "cpe:2.3:a:papercut:papercut_ng:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "9E727ABD-0007-424D-AB07-FB7816E43792",
"versionEndExcluding": "25.0.12",
"versionStartIncluding": "25.0.2"
},
{
"criteria": "cpe:2.3:a:papercut:papercut_ng:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "3938B71A-CB14-4017-A037-7D5F08DAFB13",
"versionEndExcluding": "26.0.4",
"versionStartIncluding": "26.0.2"
}
],
"operator": "OR"
}
]
}
],
"sourceIdentifier": "eb41dac7-0af8-4f84-9f6d-0272772514f4",
"cisaRequiredAction": "Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.",
"cisaVulnerabilityName": "PaperCut NG/MF Unsafe Reflection Vulnerability"
}