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CVE-2026-59886

Estado: AnalizadaAlta (7.5)—

pyasn1 is a generic ASN.1 library for Python. Prior to 0.6.4, the univ.Real type converted its mantissa, base, and exponent value to a Python float using exact big-integer exponentiation. A BER, CER, or DER encoded REAL value only a few bytes long can carry a very large exponent, causing float conversion through prettyPrint(), str(), comparison, arithmetic, int(), or an explicit float() call to consume excessive CPU and memory and hang applications that decode untrusted ASN.1 data and then print, log, or compare decoded objects. This issue is fixed in version 0.6.4.

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/UI:N indica explotación remota sin privilegios (T1190). CWE-400/770 y descripción confirman DoS por consumo excesivo de CPU/memoria al decodificar datos ASN.1 malformados (T1499.004).

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

Filter Network TrafficVulnerability ScanningPrivileged Account ManagementNetwork SegmentationLimit Access to Resource Over NetworkApplication Isolation and Sandboxing

Tecnologías afectadas (1)

Pyasn1 — Pyasn1

CWE

Referencias

JSON original (NVD)

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{
  "id": "CVE-2026-59886",
  "cveTags": [],
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          "role": "CISA Coordinator",
          "options": [
            {
              "exploitation": "none"
            },
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              "automatable": "yes"
            },
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          ],
          "version": "2.0.3",
          "timestamp": "2026-07-15T15:43:46.620953Z"
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          "integrityImpact": "NONE",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "confidentialityImpact": "NONE"
        },
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        "exploitabilityScore": 3.9
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  "published": "2026-07-14T17:17:15.010",
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    }
  ],
  "lastModified": "2026-07-21T14:38:13.080",
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