{
  "crds_version": "0.1",
  "kind": "base",
  "id": "crds:cve-2025-20333",
  "revision": 1,
  "title": "Cisco Secure Firewall ASA and FTD — VPN web server overflow",
  "summary": "The virtual private network (VPN) web server in Cisco's Secure Firewall software (ASA, FTD) does not validate request input, so an authenticated attacker overflows a buffer and runs code on the appliance.",
  "source_type": "cve",
  "severity": "critical",
  "cvss": {
    "score": 9.9,
    "vector": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
    "version": "3.1"
  },
  "epss": 0.70651,
  "exploitation": {
    "known_exploited": true,
    "exploit_available": false,
    "attack_complexity": "low",
    "kev_added": "2025-09-25",
    "prerequisites": "An authenticated session on the appliance's virtual private network web server."
  },
  "remediation": {
    "patch_available": true
  },
  "mitre_attack": [
    "T1190"
  ],
  "kill_chain": "execution",
  "recommended_action": "Apply Cisco advisory cisco-sa-asaftd-webvpn-z5xP8EUB together with the companion authorization fix now; the pair is under active attack.",
  "confidence": "high",
  "provenance": [
    {
      "fields": [
        "cvss",
        "exploitation.attack_complexity",
        "exploitation.exploit_available",
        "references",
        "published_at"
      ],
      "source": "https://nvd.nist.gov/vuln/detail/CVE-2025-20333",
      "retrieved_at": "2026-09-24T08:51:39.744Z",
      "confidence": "high",
      "extractor": "scrty-crds-pipeline/0.1"
    },
    {
      "fields": [
        "exploitation.known_exploited",
        "exploitation.kev_added"
      ],
      "source": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog",
      "retrieved_at": "2026-09-24T08:51:39.744Z",
      "confidence": "high",
      "extractor": "scrty-crds-pipeline/0.1"
    },
    {
      "fields": [
        "epss"
      ],
      "source": "https://api.first.org/data/v1/epss?cve=CVE-2025-20333",
      "retrieved_at": "2026-09-24T08:51:39.744Z",
      "confidence": "high",
      "extractor": "scrty-crds-pipeline/0.1"
    },
    {
      "fields": [
        "title",
        "summary",
        "severity",
        "remediation",
        "mitre_attack",
        "kill_chain",
        "recommended_action",
        "confidence",
        "tags",
        "exploitation.prerequisites"
      ],
      "source": "https://nvd.nist.gov/vuln/detail/CVE-2025-20333",
      "retrieved_at": "2026-09-24T08:51:39.744Z",
      "confidence": "high",
      "extractor": "claude-code"
    }
  ],
  "references": [
    {
      "type": "cve",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-20333",
      "label": "NVD record"
    },
    {
      "type": "cisa",
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog",
      "label": "CISA Known Exploited Vulnerabilities catalog"
    },
    {
      "type": "vendor_advisory",
      "url": "https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-webvpn-z5xP8EUB"
    },
    {
      "type": "vendor_advisory",
      "url": "https://sec.cloudapps.cisco.com/security/center/resources/asa_ftd_continued_attacks"
    }
  ],
  "published_at": "2025-09-25T16:15:32.073Z",
  "issued_at": "2026-09-24T08:51:39.744Z",
  "tags": [
    "cisco",
    "asa",
    "ftd",
    "vpn",
    "buffer-overflow",
    "kev"
  ]
}