FKIE_CVE-2026-20039
Vulnerability from fkie_nvd - Published: 2026-03-04 18:16 - Updated: 2026-06-17 10:16
Severity
Summary
A vulnerability in the VPN web server of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device.
This vulnerability is due to ineffective memory management of the VPN web server. An attacker could exploit this vulnerability by sending a large number of crafted HTTP requests to an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.
References
Impacted products
{
"affected": [
{
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"value": "Una vulnerabilidad en el servidor web VPN de Cisco Secure Firewall Adaptive Security Appliance (ASA) Software y Cisco Secure Firewall Threat Defense (FTD) Software podr\u00eda permitir a un atacante remoto no autenticado causar una condici\u00f3n de denegaci\u00f3n de servicio (DoS) en un dispositivo afectado.\n\nEsta vulnerabilidad se debe a una gesti\u00f3n de memoria ineficaz del servidor web VPN. Un atacante podr\u00eda explotar esta vulnerabilidad enviando un gran n\u00famero de solicitudes HTTP manipuladas a un dispositivo afectado. Un exploit exitoso podr\u00eda permitir al atacante provocar que el dispositivo se reinicie, lo que resultar\u00eda en una condici\u00f3n de DoS."
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"id": "CVE-2026-20039",
"lastModified": "2026-06-17T10:16:57.360",
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},
{
"technicalImpact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-03-05T15:49:00.526123Z",
"version": "2.0.3"
}
}
]
},
"published": "2026-03-04T18:16:17.140",
"references": [
{
"source": "psirt@cisco.com",
"tags": [
"Vendor Advisory"
],
"url": "https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-vpn-dos-SpOFF2Re"
}
],
"sourceIdentifier": "psirt@cisco.com",
"vulnStatus": "Analyzed",
"weaknesses": [
{
"description": [
{
"lang": "en",
"value": "CWE-244"
}
],
"source": "psirt@cisco.com",
"type": "Secondary"
}
]
}
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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