CVE-2021-36770
Estado: ModificadaAlta (7.8)—
Encode.pm, distribuido en Perl versiones hasta 5.34.0, permite a usuarios locales alcanzar privilegios por medio de una biblioteca Encode::ConfigLocal (en el directorio de trabajo actual) que se adelanta a una carga dinámica de módulos. Una explotación requiere una configuración inusual, y determinadas versiones 2021 de Encode.pm (3.05 hasta 3.11). Este problema ocurre porque el operador || evalúa @INC en un contexto escalar, y por lo tanto @INC sólo tiene un valor entero
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- Puntuación base: 7.8
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 1.39%
- Percentil entre todas las CVEs puntuadas: 72
- Fecha de la puntuación: 11/10/2026
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).
Tecnologías afectadas (2)
CWE
- CWE-427
Referencias
- https://github.com/Perl/perl5/commit/c1a937fef07c061600a0078f4cb53fe9c2136bb9
- https://github.com/dankogai/p5-encode/commit/527e482dc70b035d0df4f8c77a00d81f8d775c74
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5NDGQSGMEZ75FJGBKNYC75OTO7TF7XHB/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6KOZYD7BH2DNIAEZ2ZL4PJ4QUVQI6Y33/
- https://metacpan.org/dist/Encode/changes
- https://news.cpanel.com/unscheduled-tsr-10-august-2021/
- https://security-tracker.debian.org/tracker/CVE-2021-36770
- https://security.netapp.com/advisory/ntap-20210909-0003/
- https://github.com/Perl/perl5/commit/c1a937fef07c061600a0078f4cb53fe9c2136bb9
- https://github.com/dankogai/p5-encode/commit/527e482dc70b035d0df4f8c77a00d81f8d775c74
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5NDGQSGMEZ75FJGBKNYC75OTO7TF7XHB/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6KOZYD7BH2DNIAEZ2ZL4PJ4QUVQI6Y33/
- https://metacpan.org/dist/Encode/changes
- https://news.cpanel.com/unscheduled-tsr-10-august-2021/
- https://security-tracker.debian.org/tracker/CVE-2021-36770
- https://security.netapp.com/advisory/ntap-20210909-0003/
- https://security.netapp.com/advisory/ntap-20241108-0002/
JSON original (NVD)
Mostrar
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"cveTags": [],
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"accessVector": "NETWORK",
"vectorString": "AV:N/AC:M/Au:N/C:P/I:P/A:P",
"authentication": "NONE",
"integrityImpact": "PARTIAL",
"accessComplexity": "MEDIUM",
"availabilityImpact": "PARTIAL",
"confidentialityImpact": "PARTIAL"
},
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"published": "2021-08-11T23:15:07.707",
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"vulnStatus": "Modified",
"weaknesses": [
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"type": "Primary",
"source": "nvd@nist.gov",
"description": [
{
"lang": "en",
"value": "CWE-427"
}
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],
"descriptions": [
{
"lang": "en",
"value": "Encode.pm, as distributed in Perl through 5.34.0, allows local users to gain privileges via a Trojan horse Encode::ConfigLocal library (in the current working directory) that preempts dynamic module loading. Exploitation requires an unusual configuration, and certain 2021 versions of Encode.pm (3.05 through 3.11). This issue occurs because the || operator evaluates @INC in a scalar context, and thus @INC has only an integer value."
},
{
"lang": "es",
"value": "Encode.pm, distribuido en Perl versiones hasta 5.34.0, permite a usuarios locales alcanzar privilegios por medio de una biblioteca Encode::ConfigLocal (en el directorio de trabajo actual) que se adelanta a una carga dinámica de módulos. Una explotación requiere una configuración inusual, y determinadas versiones 2021 de Encode.pm (3.05 hasta 3.11). Este problema ocurre porque el operador || evalúa @INC en un contexto escalar, y por lo tanto @INC sólo tiene un valor entero"
}
],
"lastModified": "2026-06-17T03:59:08.280",
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}