CVE-2026-49440
Deno is a JavaScript, TypeScript, and WebAssembly runtime. Prior to 2.8.1, node:crypto.checkPrime(candidate[, options][, callback]) and crypto.checkPrimeSync(candidate[, options]) ran no Miller-Rabin rounds at all when the caller left options.checks at its default of 0. In that mode, the only test applied to the candidate was trial division by the primes up to 17,863. Any composite whose smallest prime factor exceeds that bound — for example the product of two primes just above it, such as 17,881 × 17,891 — was reported as true ("probably prime"). The same divergence affected the lower-level op_node_check_prime / op_node_check_prime_bytes paths that the polyfill calls into. This vulnerability is fixed in 2.8.1.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
- Puntuación base: 7.4
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.24%
- Percentil entre todas las CVEs puntuadas: 13
- 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
T1190Exploit Public-Facing Applicationinitial access60 %
Inferido por reglas deterministas a partir del vector CVSS y la CWE. Solo orientativo.
🛡️ Mitigaciones ATT&CK que cubren estas técnicas
Tecnologías afectadas (1)
CWE
- CWE-325
Referencias
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-49440",
"cveTags": [],
"metrics": {
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2026-49440",
"role": "CISA Coordinator",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "total"
}
],
"version": "2.0.3",
"timestamp": "2026-06-25T03:55:49.551538Z"
}
}
],
"cvssMetricV31": [
{
"type": "Secondary",
"source": "security-advisories@github.com",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 7.4,
"attackVector": "NETWORK",
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N",
"integrityImpact": "HIGH",
"userInteraction": "NONE",
"attackComplexity": "HIGH",
"availabilityImpact": "NONE",
"privilegesRequired": "NONE",
"confidentialityImpact": "HIGH"
},
"impactScore": 5.2,
"exploitabilityScore": 2.2
}
]
},
"affected": [
{
"source": "security-advisories@github.com",
"affectedData": [
{
"vendor": "denoland",
"product": "deno",
"versions": [
{
"status": "affected",
"version": "< 2.8.1"
}
]
}
]
}
],
"published": "2026-06-23T18:18:03.563",
"references": [
{
"url": "https://github.com/denoland/deno/pull/34391",
"tags": [
"Issue Tracking"
],
"source": "security-advisories@github.com"
},
{
"url": "https://github.com/denoland/deno/security/advisories/GHSA-9xg4-qhm4-g43w",
"tags": [
"Third Party Advisory"
],
"source": "security-advisories@github.com"
}
],
"vulnStatus": "Analyzed",
"weaknesses": [
{
"type": "Secondary",
"source": "security-advisories@github.com",
"description": [
{
"lang": "en",
"value": "CWE-325"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "Deno is a JavaScript, TypeScript, and WebAssembly runtime. Prior to 2.8.1, node:crypto.checkPrime(candidate[, options][, callback]) and crypto.checkPrimeSync(candidate[, options]) ran no Miller-Rabin rounds at all when the caller left options.checks at its default of 0. In that mode, the only test applied to the candidate was trial division by the primes up to 17,863. Any composite whose smallest prime factor exceeds that bound — for example the product of two primes just above it, such as 17,881 × 17,891 — was reported as true (\"probably prime\"). The same divergence affected the lower-level op_node_check_prime / op_node_check_prime_bytes paths that the polyfill calls into. This vulnerability is fixed in 2.8.1."
}
],
"lastModified": "2026-06-26T19:27:37.667",
"configurations": [
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:a:deno:deno:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "91F453C2-277C-4350-8234-700B47587E97",
"versionEndExcluding": "2.8.1"
}
],
"operator": "OR"
}
]
}
],
"sourceIdentifier": "security-advisories@github.com"
}