CVE-2026-42155
Full vulnerability record from the local CVENow database.
Description
Magento Long Term Support (LTS) is an unofficial, community-driven project provides an alternative to the Magento Community Edition e-commerce platform with a high level of backward compatibility. Prior to 20.18.0, the XML-RPC / SOAP API session ID is generated using an outdated, time-based construction rather than a Cryptographically Secure Pseudo-Random Number Generator (CSPRNG). All inputs to the MD5 hash are time-derived and non-secure. Because the resulting digest relies entirely on the timestamp and the PHP internal LCG state, the effective entropy is severely constrained. This violates the OWASP ASVS v4 requirement of ≥ 64 bits of entropy (V3.2.2) and NIST SP 800-63B standards. By narrowing the LCG window (via server state leaks or general predictability) and leveraging the lack of API rate-limiting, an attacker can generate a localized pool of candidate MD5 hashes and execute a high-speed online brute-force attack to hijack active API sessions. This vulnerability is fixed in 20.18.0.
View original CVE JSON
{
"id": "CVE-2026-42155",
"sourceIdentifier": "[email protected]",
"published": "2026-05-15T17:16:46.613",
"lastModified": "2026-10-26T14:10:00.130",
"vulnStatus": "Deferred",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "Magento Long Term Support (LTS) is an unofficial, community-driven project provides an alternative to the Magento Community Edition e-commerce platform with a high level of backward compatibility. Prior to 20.18.0, the XML-RPC / SOAP API session ID is generated using an outdated, time-based construction rather than a Cryptographically Secure Pseudo-Random Number Generator (CSPRNG). All inputs to the MD5 hash are time-derived and non-secure. Because the resulting digest relies entirely on the timestamp and the PHP internal LCG state, the effective entropy is severely constrained. This violates the OWASP ASVS v4 requirement of ≥ 64 bits of entropy (V3.2.2) and NIST SP 800-63B standards. By narrowing the LCG window (via server state leaks or general predictability) and leveraging the lack of API rate-limiting, an attacker can generate a localized pool of candidate MD5 hashes and execute a high-speed online brute-force attack to hijack active API sessions. This vulnerability is fixed in 20.18.0."
},
{
"lang": "es",
"value": "Magento Long Term Support (LTS) es un proyecto no oficial, impulsado por la comunidad, que proporciona una alternativa a la plataforma de comercio electrónico Magento Community Edition con un alto nivel de compatibilidad con versiones anteriores. Antes de la versión 20.18.0, el ID de sesión de la API XML-RPC / SOAP se genera utilizando una construcción obsoleta basada en el tiempo en lugar de un Generador de Números Pseudoaleatorios Criptográficamente Seguro (CSPRNG). Todas las entradas al hash MD5 se derivan del tiempo y no son seguras. Debido a que el resumen resultante depende completamente de la marca de tiempo y del estado interno LCG de PHP, la entropía efectiva está severamente restringida. Esto viola el requisito de OWASP ASVS v4 de ? 64 bits de entropía (V3.2.2) y los estándares NIST SP 800-63B. Al reducir la ventana LCG (mediante fugas de estado del servidor o previsibilidad general) y aprovechando la falta de limitación de velocidad de la API, un atacante puede generar un conjunto localizado de hashes MD5 candidatos y ejecutar un ataque de fuerza bruta en línea de alta velocidad para secuestrar sesiones de API activas. Esta vulnerabilidad se corrigió en la versión 20.18.0."
}
],
"affected": [
{
"source": "[email protected]",
"affectedData": [
{
"vendor": "OpenMage",
"product": "magento-lts",
"versions": [
{
"version": "< 20.18.0",
"status": "affected"
}
]
}
]
}
],
"metrics": {
"cvssMetricV40": [
{
"source": "[email protected]",
"type": "Secondary",
"cvssData": {
"version": "4.0",
"vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:L/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:X",
"baseScore": 9.3,
"baseSeverity": "CRITICAL",
"attackVector": "NETWORK",
"attackComplexity": "LOW",
"attackRequirements": "NONE",
"privilegesRequired": "NONE",
"userInteraction": "NONE",
"vulnConfidentialityImpact": "HIGH",
"vulnIntegrityImpact": "HIGH",
"vulnAvailabilityImpact": "LOW",
"subConfidentialityImpact": "NONE",
"subIntegrityImpact": "NONE",
"subAvailabilityImpact": "NONE",
"exploitMaturity": "NOT_DEFINED",
"confidentialityRequirement": "NOT_DEFINED",
"integrityRequirement": "NOT_DEFINED",
"availabilityRequirement": "NOT_DEFINED",
"modifiedAttackVector": "NOT_DEFINED",
"modifiedAttackComplexity": "NOT_DEFINED",
"modifiedAttackRequirements": "NOT_DEFINED",
"modifiedPrivilegesRequired": "NOT_DEFINED",
"modifiedUserInteraction": "NOT_DEFINED",
"modifiedVulnConfidentialityImpact": "NOT_DEFINED",
"modifiedVulnIntegrityImpact": "NOT_DEFINED",
"modifiedVulnAvailabilityImpact": "NOT_DEFINED",
"modifiedSubConfidentialityImpact": "NOT_DEFINED",
"modifiedSubIntegrityImpact": "NOT_DEFINED",
"modifiedSubAvailabilityImpact": "NOT_DEFINED",
"Safety": "NOT_DEFINED",
"Automatable": "NOT_DEFINED",
"Recovery": "NOT_DEFINED",
"valueDensity": "NOT_DEFINED",
"vulnerabilityResponseEffort": "NOT_DEFINED",
"providerUrgency": "NOT_DEFINED"
}
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"timestamp": "2026-05-15T17:36:24.561394Z",
"id": "CVE-2026-42155",
"options": [
{
"exploitation": "poc"
},
{
"automatable": "yes"
},
{
"technicalImpact": "total"
}
],
"role": "CISA Coordinator",
"version": "2.0.3"
}
}
]
},
"weaknesses": [
{
"source": "[email protected]",
"type": "Secondary",
"description": [
{
"lang": "en",
"value": "CWE-330"
},
{
"lang": "en",
"value": "CWE-331"
},
{
"lang": "en",
"value": "CWE-338"
}
]
}
],
"references": [
{
"url": "https://github.com/OpenMage/magento-lts/security/advisories/GHSA-2cwr-gcf9-pvxr",
"source": "[email protected]"
},
{
"url": "https://github.com/OpenMage/magento-lts/security/advisories/GHSA-2cwr-gcf9-pvxr",
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"
}
]
}