{"cve":{"cve_id":"CVE-2023-27351","is_kev":true,"kev_date_added":"2026-04-20","kev_vendor_project":"PaperCut","kev_product":"NG/MF","kev_vulnerability_name":"PaperCut NG/MF Improper Authentication Vulnerability","kev_short_description":"PaperCut NG/MF contains an improper authentication vulnerability that could allow remote attackers to bypass authentication on affected installations via the SecurityRequestFilter class.","kev_required_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.","kev_due_date":"2026-05-04","kev_known_ransomware":true,"kev_notes":"https://www.papercut.com/kb/Main/PO-1216-and-PO-1219 ; https://nvd.nist.gov/vuln/detail/CVE-2023-27351","kev_cwes":["CWE-287"],"epss_score":0.7842,"epss_percentile":0.99526,"epss_as_of":"2026-06-23","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.","published_at":"2023-04-20T00:00:00Z","last_modified_at":null,"cvss_v3_score":8.2,"cvss_v3_vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N","cvss_v3_severity":"HIGH","cvss_v4_score":null,"cvss_v4_vector":null,"cvss_v4_severity":null,"ssvc_decision":null,"ssvc_exploitation":"active","ssvc_automatable":true,"ssvc_technical_impact":"partial","cwes":["CWE-287"],"nvd_references":["https://www.papercut.com/kb/Main/PO-1216-and-PO-1219","https://www.zerodayinitiative.com/advisories/ZDI-23-232/"],"vuln_status":null,"trending_score":null,"is_trending":false,"has_trended":false,"trended_number_one":false,"trending_peak_score":null,"trending_peak_rank":null,"started_trending_at":null,"trended_number_one_at":null,"summary_generated":null,"summary_generated_at":null,"summary_model":null,"created_at":"2026-06-24T00:09:31.350578Z","updated_at":"2026-06-29T01:28:33.973490Z"},"effective_severity":"HIGH","badges":["kev","ransomware","poc","epss"],"impact_analysis":[],"cvss_v3_decoded":{"version":"3.0","metrics":[{"metric":"AV","name":"Attack Vector","value":"N","value_label":"Network"},{"metric":"AC","name":"Attack Complexity","value":"L","value_label":"Low"},{"metric":"PR","name":"Privileges Required","value":"N","value_label":"None"},{"metric":"UI","name":"User Interaction","value":"N","value_label":"None"},{"metric":"S","name":"Scope","value":"U","value_label":"Unchanged"},{"metric":"C","name":"Confidentiality","value":"H","value_label":"High"},{"metric":"I","name":"Integrity","value":"L","value_label":"Low"},{"metric":"A","name":"Availability","value":"N","value_label":"None"}]},"cvss_v4_decoded":{"version":null,"metrics":[]},"affected":[{"vendor_slug":"papercut","vendor_name":"PaperCut","product_slug":"ng","product_name":"NG","version_start":"22.0.5 (Build 63914)","version_start_inclusive":true,"version_end":"22.0.5 (Build 63914)","version_end_inclusive":true,"cpe23_uri":"cve5:papercut:ng:22.0.5 (Build 63914):22.0.5 (Build 63914)"}],"exploit_refs":[{"source":"nuclei","kind":"nuclei","url":"https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2023/CVE-2023-27351.yaml","title":"PaperCut NG - Authentication Bypass","author":"daffainfo,jjcho","disclosed_at":null}],"news":[],"references":[{"url":"https://www.papercut.com/kb/Main/PO-1216-and-PO-1219","source_type":"MISC","tags":[]},{"url":"https://www.zerodayinitiative.com/advisories/ZDI-23-232/","source_type":"VENDOR_ADVISORY","tags":["advisory"]}],"timeline":[{"type":"published","at":"2023-04-20T00:00:00Z","label":"CVE published","source":null},{"type":"cisa_reported","at":"2026-04-20T00:00:00Z","label":"Added to CISA KEV catalog","source":"kev"},{"type":"poc_available","at":"2026-06-24T00:29:48.638073Z","label":"Public PoC available","source":"nuclei"},{"type":"cvss_changed","at":"2026-06-28T17:27:24.170440Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"cvss_changed","at":"2026-06-28T17:27:24.170440Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"cvss_changed","at":"2026-06-28T17:27:24.170440Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"ssvc_changed","at":"2026-06-29T01:28:33.973490Z","label":"SSVC decision revised","source":"vulnrichment"},{"type":"ssvc_changed","at":"2026-06-29T01:28:33.973490Z","label":"SSVC decision revised","source":"vulnrichment"},{"type":"ssvc_changed","at":"2026-06-29T01:28:33.973490Z","label":"SSVC decision revised","source":"vulnrichment"}]}