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CVE-2026-8376

Estado: ModificadaCrítica (9.8)—

Perl versions before 5.40.5-RC1, from 5.41.0 before 5.42.3-RC1, from 5.43.0 before 5.43.11 have a heap buffer overflow when compiling regular expressions with a repeated fixed string on 32-bit builds.

Perl_study_chunk in regcomp_study.c checked the size of the joined substring buffer in characters rather than bytes. For a quantified fixed substring with a large minimum count, the byte length mincount * l could overflow SSize_t, producing an undersized SvGROW allocation; the subsequent copy writes past the end of the buffer.

A caller that compiles an attacker-controlled regular expression on a 32-bit perl build triggers a heap buffer overflow at compile time.

CVSS

Probabilidad de explotación (EPSS)

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.

Vector CVSS AV:N/AC:L/PR:N permite explotación remota sin autenticación (T1190). Overflow en compilación de regex permite ejecución de código arbitrario (T1059).

Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.

🛡️ Mitigaciones ATT&CK que cubren estas técnicas

Privileged Account ManagementVulnerability ScanningRestrict Web-Based ContentNetwork SegmentationLimit Software InstallationLimit Access to Resource Over Network

Tecnologías afectadas (1)

Perl — Perl

CWE

Referencias

JSON original (NVD)

Mostrar
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  "id": "CVE-2026-8376",
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          "version": "2.0.3",
          "timestamp": "2026-05-27T18:03:45.554441Z"
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          "integrityImpact": "HIGH",
          "userInteraction": "NONE",
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          "privilegesRequired": "NONE",
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  "published": "2026-05-26T00:16:57.150",
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      "value": "Perl versions before 5.40.5-RC1, from 5.41.0 before 5.42.3-RC1, from 5.43.0 before 5.43.11 have a heap buffer overflow when compiling regular expressions with a repeated fixed string on 32-bit builds.\n\nPerl_study_chunk in regcomp_study.c checked the size of the joined substring buffer in characters rather than bytes. For a quantified fixed substring with a large minimum count, the byte length mincount * l could overflow SSize_t, producing an undersized SvGROW allocation; the subsequent copy writes past the end of the buffer.\n\nA caller that compiles an attacker-controlled regular expression on a 32-bit perl build triggers a heap buffer overflow at compile time."
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      "value": "Versiones de Perl hasta la 5.43.10 tienen un desbordamiento de búfer de montón al compilar expresiones regulares con una cadena fija repetida en compilaciones de 32 bits.\n\nPerl_study_chunk en regcomp_study.c verificó el tamaño del búfer de subcadena unida en caracteres en lugar de bytes. Para una subcadena fija cuantificada con un recuento mínimo grande, la longitud en bytes mincount * l podría desbordar SSize_t, produciendo una asignación SvGROW de tamaño insuficiente; la copia subsiguiente escribe más allá del final del búfer.\n\nUn llamador que compila una expresión regular controlada por el atacante en una compilación de Perl de 32 bits desencadena un desbordamiento de búfer de montón en tiempo de compilación."
    }
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  "lastModified": "2026-09-08T22:19:18.373",
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