CVE-2026-74997
In Roundcube Webmail before 1.6.18 and 1.7.x before 1.7.3, the cmd_learn driver of the markasjunk plugin is subject to remote code execution via crafted placeholder replacement values. This issue only affects Roundcube instances using the markasjunk plugin with its cmd_learn driver.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- Puntuación base: 8.8
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 1.13%
- Percentil entre todas las CVEs puntuadas: 65
- 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).
🎯 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
T1059Command and Scripting Interpreterexecution90 %
Vector AV:N/AC:L/PR:L permite acceso remoto con privilegios (usuario autenticado). CWE-78 (command injection) + descripción de RCE vía sustitución de placeholders en el plugin markasjunk confirma ejecución remota de comandos.
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 (1)
CWE
- CWE-78
Referencias
- https://github.com/roundcube/roundcubemail/commit/14044f843cfacbe78b042f659e379d6b4497aa7c
- https://github.com/roundcube/roundcubemail/commit/495d211638f222336b20f4744545c53712426c2a
- https://github.com/roundcube/roundcubemail/commit/b8f90e28a46d42e79a69568cba897f8f4223d9cd
- https://github.com/roundcube/roundcubemail/releases/tag/1.6.18
- https://github.com/roundcube/roundcubemail/releases/tag/1.7.3
- https://roundcube.net/news/2026/08/09/security-updates-1.6.18-and-1.7.3
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-74997",
"cveTags": [],
"metrics": {
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2026-74997",
"role": "CISA Coordinator",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "total"
}
],
"version": "2.0.3",
"timestamp": "2026-08-17T14:34:16.294775Z"
}
}
],
"cvssMetricV31": [
{
"type": "Secondary",
"source": "cve@mitre.org",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 8.8,
"attackVector": "NETWORK",
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"integrityImpact": "HIGH",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "LOW",
"confidentialityImpact": "HIGH"
},
"impactScore": 5.9,
"exploitabilityScore": 2.8
}
]
},
"affected": [
{
"source": "cve@mitre.org",
"affectedData": [
{
"vendor": "Roundcube",
"product": "Webmail",
"versions": [
{
"status": "affected",
"version": "1.6.0",
"lessThan": "1.6.18",
"versionType": "semver"
},
{
"status": "affected",
"version": "1.7.0",
"lessThan": "1.7.3",
"versionType": "semver"
}
],
"defaultStatus": "unaffected"
}
]
}
],
"published": "2026-08-17T13:16:54.100",
"references": [
{
"url": "https://github.com/roundcube/roundcubemail/commit/14044f843cfacbe78b042f659e379d6b4497aa7c",
"tags": [
"Patch"
],
"source": "cve@mitre.org"
},
{
"url": "https://github.com/roundcube/roundcubemail/commit/495d211638f222336b20f4744545c53712426c2a",
"tags": [
"Patch"
],
"source": "cve@mitre.org"
},
{
"url": "https://github.com/roundcube/roundcubemail/commit/b8f90e28a46d42e79a69568cba897f8f4223d9cd",
"tags": [
"Patch"
],
"source": "cve@mitre.org"
},
{
"url": "https://github.com/roundcube/roundcubemail/releases/tag/1.6.18",
"tags": [
"Release Notes"
],
"source": "cve@mitre.org"
},
{
"url": "https://github.com/roundcube/roundcubemail/releases/tag/1.7.3",
"tags": [
"Release Notes"
],
"source": "cve@mitre.org"
},
{
"url": "https://roundcube.net/news/2026/08/09/security-updates-1.6.18-and-1.7.3",
"tags": [
"Vendor Advisory"
],
"source": "cve@mitre.org"
}
],
"vulnStatus": "Analyzed",
"weaknesses": [
{
"type": "Secondary",
"source": "cve@mitre.org",
"description": [
{
"lang": "en",
"value": "CWE-78"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "In Roundcube Webmail before 1.6.18 and 1.7.x before 1.7.3, the cmd_learn driver of the markasjunk plugin is subject to remote code execution via crafted placeholder replacement values. This issue only affects Roundcube instances using the markasjunk plugin with its cmd_learn driver."
}
],
"lastModified": "2026-09-08T19:09:05.140",
"configurations": [
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:a:roundcube:webmail:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "D51A5415-8AC6-49A9-AAA8-9ED72D9A551E",
"versionEndExcluding": "1.6.18",
"versionStartIncluding": "1.6.0"
},
{
"criteria": "cpe:2.3:a:roundcube:webmail:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "D5C9B7FB-8223-444C-B728-6E724AC2F0C9",
"versionEndExcluding": "1.7.3",
"versionStartIncluding": "1.7.0"
}
],
"operator": "OR"
}
]
}
],
"sourceIdentifier": "cve@mitre.org"
}