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CVE-2020-7461

Status: ModifiedHigh (7.3)—💥 PoC

In FreeBSD 12.1-STABLE before r365010, 11.4-STABLE before r365011, 12.1-RELEASE before p9, 11.4-RELEASE before p3, and 11.3-RELEASE before p13, dhclient(8) fails to handle certain malformed input related to handling of DHCP option 119 resulting a heap overflow. The heap overflow could in principle be exploited to achieve remote code execution. The affected process runs with reduced privileges in a Capsicum sandbox, limiting the immediate impact of an exploit.

CVSS

Exploitation probability (EPSS)

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).

💥 Public exploits

Exploit code or detection templates are publicly available. This is not the same as confirmed active exploitation (KEV), but it raises the risk: patch with priority.

⚠️ GitHub proofs of concept are not verified: some are fake or contain malware. Never run them outside an isolated lab.

Affected technologies (3)

CWEs

References

Raw JSON (NVD)

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{
  "id": "CVE-2020-7461",
  "cveTags": [],
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  "published": "2021-03-26T21:15:13.053",
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      "value": "In FreeBSD 12.1-STABLE before r365010, 11.4-STABLE before r365011, 12.1-RELEASE before p9, 11.4-RELEASE before p3, and 11.3-RELEASE before p13, dhclient(8) fails to handle certain malformed input related to handling of DHCP option 119 resulting a heap overflow. The heap overflow could in principle be exploited to achieve remote code execution. The affected process runs with reduced privileges in a Capsicum sandbox, limiting the immediate impact of an exploit."
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      "value": "En FreeBSD versiones 12.1-STABLE anteriores a r365010, 11.4-STABLE anteriores a r365011, 12.1-RELEASE anteriores a p9, 11.4-RELEASE anteriores a p3 y 11.3-RELEASE anteriores a p13, dhclient(8) no puede manejar determinadas entradas malformadas relacionadas con el manejo de la opción 119 de DHCP resultando en un desbordamiento de la pila. En principio, el desbordamiento de la pila podría explotarse para lograr una ejecución de código remota. El proceso afectado se ejecuta con privilegios reducidos en un sandbox Capsicum, limitando el impacto inmediato de una explotación."
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  "lastModified": "2026-06-17T03:24:49.540",
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