{
  "id": "CVE-2023-27351",
  "url": "https://spydr.io/cve/CVE-2023-27351",
  "published": "2023-04-20T16:15:07.723Z",
  "modified": "2026-10-01T19:17:14.823Z",
  "score": 7.5,
  "severity": "high",
  "cvss_version": "3.1",
  "vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
  "score_source": "NVD",
  "epss": 0.78052,
  "epss_percentile": 0.99566,
  "exploited": true,
  "kev": {
    "added": "2026-04-20",
    "due": "2026-05-04",
    "action": "Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.",
    "ransomware": "Known",
    "name": "PaperCut NG/MF Improper Authentication Vulnerability",
    "notes": "https://www.papercut.com/kb/Main/PO-1216-and-PO-1219 ; https://nvd.nist.gov/vuln/detail/CVE-2023-27351"
  },
  "ssvc_exploitation": "active",
  "vendors": [
    "PaperCut"
  ],
  "products": [
    "PaperCut NG"
  ],
  "cwes": [
    "CWE-287"
  ],
  "description": "This vulnerability allows remote attackers to bypass authentication on affected installations of PaperCut NG 22.0.5 (Build 63914). Authentication is not required to exploit this vulnerability. The specific flaw exists within the SecurityRequestFilter class. The issue results from improper implementation of the authentication algorithm. An attacker can leverage this vulnerability to bypass authentication on the system. Was ZDI-CAN-19226.",
  "status": "Analyzed",
  "score_type": "Primary",
  "scores": {
    "cvss_v40": null,
    "cvss_v31": 7.5,
    "cvss_v30": 8.2
  },
  "references": [
    {
      "url": "https://www.papercut.com/kb/Main/PO-1216-and-PO-1219",
      "tags": [
        "Vendor Advisory"
      ]
    },
    {
      "url": "https://www.zerodayinitiative.com/advisories/ZDI-23-232/",
      "tags": [
        "Third Party Advisory",
        "VDB Entry"
      ]
    },
    {
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-27351",
      "tags": [
        "US Government Resource"
      ]
    }
  ],
  "nvd_url": "https://nvd.nist.gov/vuln/detail/CVE-2023-27351",
  "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."
    }
  ]
}