CVE-2026-49406
Full vulnerability record from the local CVENow database.
Description
Deno is a JavaScript, TypeScript, and WebAssembly runtime. Prior to 2.7.12, when Deno was run in BYONM mode (nodeModulesDir: "manual"), the module resolver did not validate that a package's resolved entrypoint stayed within its node_modules/<pkg>/ directory. A malicious package.json whose main field contained .. segments was able to resolve to an arbitrary path on disk, and the resolver then read that file without consulting the --allow-read allowlist. This let a require("evil-pkg") call return the contents of a file that a direct Deno.readTextFileSync(...) call would have been blocked from reading. This vulnerability is fixed in 2.7.12.
Severity
MEDIUM
CVSS score
5.5
(v3.1)
Vulnerability status
Analyzed
Source identifier
Published
2026-06-23 18:18:03.310000
Last modified
2026-10-25 23:10:00.167000
View original CVE JSON
{
"id": "CVE-2026-49406",
"sourceIdentifier": "[email protected]",
"published": "2026-06-23T18:18:03.310",
"lastModified": "2026-10-25T23:10:00.167",
"vulnStatus": "Analyzed",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "Deno is a JavaScript, TypeScript, and WebAssembly runtime. Prior to 2.7.12, when Deno was run in BYONM mode (nodeModulesDir: \"manual\"), the module resolver did not validate that a package's resolved entrypoint stayed within its node_modules/<pkg>/ directory. A malicious package.json whose main field contained .. segments was able to resolve to an arbitrary path on disk, and the resolver then read that file without consulting the --allow-read allowlist. This let a require(\"evil-pkg\") call return the contents of a file that a direct Deno.readTextFileSync(...) call would have been blocked from reading. This vulnerability is fixed in 2.7.12."
},
{
"lang": "es",
"value": "Deno es un entorno de ejecución de JavaScript, TypeScript y WebAssembly. Antes de la versión 2.7.12, cuando Deno se ejecutaba en modo BYONM (nodeModulesDir: ’manual’), el resolvedor de módulos no validaba que el punto de entrada resuelto de un paquete permaneciera dentro de su directorio node_modules/[pkg]/. Un package.json malicioso cuyo campo main contenía segmentos .. podía resolverse a una ruta arbitraria en el disco, y el resolvedor luego leía ese archivo sin consultar la lista de permitidos --allow-read. Esto permitía que una llamada require(’evil-pkg’) devolviera el contenido de un archivo que una llamada directa Deno.readTextFileSync(...) habría sido bloqueada para su lectura. Esta vulnerabilidad está corregida en la versión 2.7.12."
}
],
"affected": [
{
"source": "[email protected]",
"affectedData": [
{
"vendor": "denoland",
"product": "deno",
"versions": [
{
"version": "< 2.7.12",
"status": "affected"
}
]
}
]
}
],
"metrics": {
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"source": "[email protected]",
"type": "Secondary",
"cvssData": {
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"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N",
"baseScore": 5.5,
"baseSeverity": "MEDIUM",
"attackVector": "LOCAL",
"attackComplexity": "LOW",
"privilegesRequired": "LOW",
"userInteraction": "NONE",
"scope": "UNCHANGED",
"confidentialityImpact": "HIGH",
"integrityImpact": "NONE",
"availabilityImpact": "NONE"
},
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"role": "CISA Coordinator",
"version": "2.0.3"
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"weaknesses": [
{
"source": "[email protected]",
"type": "Primary",
"description": [
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"lang": "en",
"value": "CWE-22"
}
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"configurations": [
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"references": [
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"source": "[email protected]",
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