CVE-2020-5238
Estado: ModificadaMedia (6.5)—
The table extension in GitHub Flavored Markdown before version 0.29.0.gfm.1 takes O(n * n) time to parse certain inputs. An attacker could craft a markdown table which would take an unreasonably long time to process, causing a denial of service. This issue does not affect the upstream cmark project. The issue has been fixed in version 0.29.0.gfm.1.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- Puntuación base: 6.5
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 1.57%
- Percentil entre todas las CVEs puntuadas: 75
- Fecha de la puntuación: 6/10/2026
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-20
- CWE-20
Referencias
- https://github.com/github/cmark-gfm/commit/85d895289c5ab67f988ca659493a64abb5fec7b4
- https://github.com/github/cmark-gfm/security/advisories/GHSA-7gc6-9qr5-hc85
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TCDHBTUFIOYRIS5HAS6PZNBNMB7IOAX3/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WMQFOQQCWOAMQ4I2XIVCVOXXIJ75HDCW/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZGJH2A4VAV54X6NSCNNGSEIGIIY5N2VR/
- https://github.com/github/cmark-gfm/commit/85d895289c5ab67f988ca659493a64abb5fec7b4
- https://github.com/github/cmark-gfm/security/advisories/GHSA-7gc6-9qr5-hc85
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TCDHBTUFIOYRIS5HAS6PZNBNMB7IOAX3/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WMQFOQQCWOAMQ4I2XIVCVOXXIJ75HDCW/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZGJH2A4VAV54X6NSCNNGSEIGIIY5N2VR/
JSON original (NVD)
Mostrar
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"id": "CVE-2020-5238",
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"lang": "en",
"value": "The table extension in GitHub Flavored Markdown before version 0.29.0.gfm.1 takes O(n * n) time to parse certain inputs. An attacker could craft a markdown table which would take an unreasonably long time to process, causing a denial of service. This issue does not affect the upstream cmark project. The issue has been fixed in version 0.29.0.gfm.1."
},
{
"lang": "es",
"value": "La extensión de tabla en GitHub Flavored Markdown anterior a la versión 0.29.0.gfm.1 toma un tiempo O(n*n) en analizar determinadas entradas. Un atacante podría crear una tabla de descuento que tomaría un tiempo irrazonablemente largo de procesar, causando una denegación de servicio. Este problema no afecta el proyecto cmark aguas arriba. El problema se ha corregido en la versión 0.29.0.gfm.1"
}
],
"lastModified": "2026-06-17T03:21:06.427",
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