{
  "id": "CVE-2024-20353",
  "url": "https://spydr.io/cve/CVE-2024-20353",
  "published": "2024-04-24T19:15:46.723Z",
  "modified": "2026-08-11T19:33:44.513Z",
  "score": 8.6,
  "severity": "high",
  "cvss_version": "3.1",
  "vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H",
  "score_source": "NVD",
  "epss": 0.70686,
  "epss_percentile": 0.99381,
  "exploited": true,
  "kev": {
    "added": "2024-04-24",
    "due": "2024-05-01",
    "action": "Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.",
    "ransomware": "Unknown",
    "name": "Cisco ASA and FTD Denial of Service Vulnerability",
    "notes": "https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-websrvs-dos-X8gNucD2; https://nvd.nist.gov/vuln/detail/CVE-2024-20353"
  },
  "ssvc_exploitation": "active",
  "vendors": [
    "Cisco"
  ],
  "products": [
    "Cisco Adaptive Security Appliance (ASA) Software",
    "Cisco Firepower Threat Defense Software",
    "cisco asa"
  ],
  "cwes": [
    "CWE-835"
  ],
  "description": "A vulnerability in the management and VPN web servers for Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause the device to reload unexpectedly, resulting in a denial of service (DoS) condition. This vulnerability is due to incomplete error checking when parsing an HTTP header. An attacker could exploit this vulnerability by sending a crafted HTTP request to a targeted web server on a device. A successful exploit could allow the attacker to cause a DoS condition when the device reloads.",
  "status": "Analyzed",
  "score_type": "Primary",
  "scores": {
    "cvss_v40": null,
    "cvss_v31": 8.6,
    "cvss_v30": null
  },
  "references": [
    {
      "url": "https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-websrvs-dos-X8gNucD2",
      "tags": [
        "Vendor Advisory"
      ]
    },
    {
      "url": "https://blog.talosintelligence.com/arcanedoor-new-espionage-focused-campaign-found-targeting-perimeter-network-devices/",
      "tags": [
        "Exploit",
        "Third Party Advisory"
      ]
    },
    {
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2024-20353",
      "tags": [
        "US Government Resource"
      ]
    }
  ],
  "nvd_url": "https://nvd.nist.gov/vuln/detail/CVE-2024-20353",
  "covered_in": [],
  "attribution": [
    {
      "source": "NVD",
      "url": "https://nvd.nist.gov",
      "notice": "This product uses data from the NVD API but is not endorsed or certified by the NVD."
    },
    {
      "source": "CISA KEV",
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog",
      "notice": "Known exploited vulnerabilities from the CISA KEV catalog."
    },
    {
      "source": "FIRST EPSS",
      "url": "https://www.first.org/epss",
      "notice": "Exploit prediction scores from FIRST EPSS."
    }
  ]
}