NCSC-2026-0295

Vulnerability from csaf_ncscnl - Published: 2026-08-12 14:56 - Updated: 2026-08-12 14:56
Summary
Kwetsbaarheid verholpen in Cisco Secure Firewall ASA en FTD software
Notes
The Netherlands Cyber Security Center (henceforth: NCSC-NL) maintains this page to enhance access to its information and security advisories. The use of this security advisory is subject to the following terms and conditions: NCSC-NL makes every reasonable effort to ensure that the content of this page is kept up to date, and that it is accurate and complete. Nevertheless, NCSC-NL cannot entirely rule out the possibility of errors, and therefore cannot give any warranty in respect of its completeness, accuracy or continuous keeping up-to-date. The information contained in this security advisory is intended solely for the purpose of providing general information to professional users. No rights can be derived from the information provided therein. NCSC-NL and the Kingdom of the Netherlands assume no legal liability or responsibility for any damage resulting from either the use or inability of use of this security advisory. This includes damage resulting from the inaccuracy of incompleteness of the information contained in the advisory. This security advisory is subject to Dutch law. All disputes related to or arising from the use of this advisory will be submitted to the competent court in The Hague. This choice of means also applies to the court in summary proceedings.
Feiten: Cisco heeft een kwetsbaarheid verholpen in Cisco Secure Firewall ASA en FTD software.
Interpretaties: De kwetsbaarheid bevindt zich in de heap inspection binnen de Remote Access SSL VPN-service. Deze ontstaat door onvoldoende foutcontrole tijdens de verwerking van HTTP-verzoeken. Een niet-geauthenticeerde externe aanvaller kan speciaal opgemaakte HTTP-verzoeken versturen om de getroffen apparaten onverwacht te laten herstarten, wat leidt tot een Denial-of-Service. De kwetsbaarheid treft netwerkbeveiligingsapparaten die gebruikt worden voor veilige externe toegang.
Oplossingen: Cisco heeft updates uitgebracht om de kwetsbaarheid te verhelpen. Zie bijgevoegde referenties voor meer informatie.
Kans: medium
Schade: high
CWE-244: Improper Clearing of Heap Memory Before Release ('Heap Inspection')
CVE-2026-20349

A heap inspection vulnerability in Cisco Secure Firewall ASA and FTD's Remote Access SSL VPN service allows unauthenticated remote attackers to send crafted HTTP requests causing device reloads and denial of service.

8.6 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
CWE-244 - Improper Clearing of Heap Memory Before Release ('Heap Inspection')
Affected products
Product Identifier Version Remediation
vers:unknown/*
Cisco / Secure Firewall Adaptive Security Appliance (ASA) and Secure Firewall Threat Defense (FTD)
vers:unknown/*
References
To clipboard 

{
  "document": {
    "category": "csaf_security_advisory",
    "csaf_version": "2.0",
    "distribution": {
      "tlp": {
        "label": "WHITE"
      }
    },
    "lang": "nl",
    "notes": [
      {
        "category": "legal_disclaimer",
        "text": "The Netherlands Cyber Security Center (henceforth: NCSC-NL) maintains this page to enhance access to its information and security advisories. The use of this security advisory is subject to the following terms and conditions:\n\n    NCSC-NL makes every reasonable effort to ensure that the content of this page is kept up to date, and that it is accurate and complete. Nevertheless, NCSC-NL cannot entirely rule out the possibility of errors, and therefore cannot give any warranty in respect of its completeness, accuracy or continuous keeping up-to-date. The information contained in this security advisory is intended solely for the purpose of providing general information to professional users. No rights can be derived from the information provided therein.\n\n    NCSC-NL and the Kingdom of the Netherlands assume no legal liability or responsibility for any damage resulting from either the use or inability of use of this security advisory. This includes damage resulting from the inaccuracy of incompleteness of the information contained in the advisory.\n    This security advisory is subject to Dutch law. All disputes related to or arising from the use of this advisory will be submitted to the competent court in The Hague. This choice of means also applies to the court in summary proceedings."
      },
      {
        "category": "description",
        "text": "Cisco heeft een kwetsbaarheid verholpen in Cisco Secure Firewall ASA en FTD software.",
        "title": "Feiten"
      },
      {
        "category": "description",
        "text": "De kwetsbaarheid bevindt zich in de heap inspection binnen de Remote Access SSL VPN-service. Deze ontstaat door onvoldoende foutcontrole tijdens de verwerking van HTTP-verzoeken. Een niet-geauthenticeerde externe aanvaller kan speciaal opgemaakte HTTP-verzoeken versturen om de getroffen apparaten onverwacht te laten herstarten, wat leidt tot een Denial-of-Service. De kwetsbaarheid treft netwerkbeveiligingsapparaten die gebruikt worden voor veilige externe toegang.",
        "title": "Interpretaties"
      },
      {
        "category": "description",
        "text": "Cisco heeft updates uitgebracht om de kwetsbaarheid te verhelpen. Zie bijgevoegde referenties voor meer informatie.",
        "title": "Oplossingen"
      },
      {
        "category": "general",
        "text": "medium",
        "title": "Kans"
      },
      {
        "category": "general",
        "text": "high",
        "title": "Schade"
      },
      {
        "category": "general",
        "text": "Improper Clearing of Heap Memory Before Release (\u0027Heap Inspection\u0027)",
        "title": "CWE-244"
      }
    ],
    "publisher": {
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      "contact_details": "cert@ncsc.nl",
      "name": "Nationaal Cyber Security Centrum",
      "namespace": "https://www.ncsc.nl/"
    },
    "references": [
      {
        "category": "external",
        "summary": "Reference",
        "url": "https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-vpn-dos-dzv4mQFF"
      }
    ],
    "title": "Kwetsbaarheid verholpen in Cisco Secure Firewall ASA en FTD software",
    "tracking": {
      "current_release_date": "2026-08-12T14:56:37.079617Z",
      "generator": {
        "date": "2025-08-04T16:30:00Z",
        "engine": {
          "name": "V.A.",
          "version": "1.3"
        }
      },
      "id": "NCSC-2026-0295",
      "initial_release_date": "2026-08-12T14:56:37.079617Z",
      "revision_history": [
        {
          "date": "2026-08-12T14:56:37.079617Z",
          "number": "1.0.0",
          "summary": "Initiele versie"
        }
      ],
      "status": "final",
      "version": "1.0.0"
    }
  },
  "product_tree": {
    "branches": [
      {
        "branches": [
          {
            "branches": [
              {
                "category": "product_version_range",
                "name": "vers:unknown/*",
                "product": {
                  "name": "vers:unknown/*",
                  "product_id": "CSAFPID-1"
                }
              }
            ],
            "category": "product_name",
            "name": "Secure Firewall Adaptive Security Appliance (ASA) and Secure Firewall Threat Defense (FTD) "
          }
        ],
        "category": "vendor",
        "name": "Cisco"
      }
    ]
  },
  "vulnerabilities": [
    {
      "cve": "CVE-2026-20349",
      "cwe": {
        "id": "CWE-244",
        "name": "Improper Clearing of Heap Memory Before Release (\u0027Heap Inspection\u0027)"
      },
      "notes": [
        {
          "category": "other",
          "text": "Improper Clearing of Heap Memory Before Release (\u0027Heap Inspection\u0027)",
          "title": "CWE-244"
        },
        {
          "category": "description",
          "text": "A heap inspection vulnerability in Cisco Secure Firewall ASA and FTD\u0027s Remote Access SSL VPN service allows unauthenticated remote attackers to send crafted HTTP requests causing device reloads and denial of service.",
          "title": "Summary"
        }
      ],
      "product_status": {
        "known_affected": [
          "CSAFPID-1"
        ]
      },
      "references": [
        {
          "category": "self",
          "summary": "CVE-2026-20349 | NCSC-NL Website",
          "url": "https://vulnerabilities.ncsc.nl/csaf/v2/2026/cve-2026-20349.json"
        }
      ],
      "scores": [
        {
          "cvss_v3": {
            "baseScore": 8.6,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H",
            "version": "3.1"
          },
          "products": [
            "CSAFPID-1"
          ]
        }
      ],
      "title": "CVE-2026-20349"
    }
  ]
}



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