CVE-2021-36770

Status: ModifiedHigh (7.8)—

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.

CVSS

Version: 3.1
Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Base score: 7.8

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 1.39%
Percentile among all scored CVEs: 72
Score date: 10/12/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

Affected technologies (2)

Fedoraproject — Fedora P5-encode Project — P5-encode

CWEs

CWE-427

References

Raw JSON (NVD)

Show

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  "id": "CVE-2021-36770",
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      "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."
    },
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      "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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}