{"cve":{"cve_id":"CVE-2026-81578","is_kev":true,"kev_date_added":"2026-08-31","kev_vendor_project":"PaperCut","kev_product":"NG/MF","kev_vulnerability_name":"PaperCut NG/MF Missing Authentication for Critical Function Vulnerability","kev_short_description":"PaperCut NG/MF contains a missing authentication for critical function vulnerability which allows an unauthenticated remote attacker to modify certain system configurations. This vulnerability can be chained with CVE-2026-82078.","kev_required_action":"Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.","kev_due_date":"2026-09-14","kev_known_ransomware":false,"kev_notes":"https://www.papercut.com/kb/Main/security-bulletin-27-aug-2026-urgent-security-advisory/ ; BOD 26-04: https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk ; Forensics Triage Requirements: https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk ; https://nvd.nist.gov/vuln/detail/CVE-2026-81578","kev_cwes":["CWE-306"],"epss_score":0.01617,"epss_percentile":0.74719,"epss_as_of":"2026-09-15","description":"An improper access control vulnerability exists in the web management interface of PaperCut MF and PaperCut NG. Under specific conditions, unauthenticated remote requests targeting administrative functions can trigger backend actions prior to the  completion of access validation checks. This allows an unauthenticated remote attacker to modify certain system configurations.","published_at":"2026-08-28T11:39:45.402000Z","last_modified_at":"2026-09-14T00:16:56.207000Z","cvss_v3_score":9.8,"cvss_v3_vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","cvss_v3_severity":"CRITICAL","cvss_v4_score":8.8,"cvss_v4_vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:H/VA:L/SC:N/SI:N/SA:N","cvss_v4_severity":"HIGH","ssvc_decision":null,"ssvc_exploitation":"active","ssvc_automatable":true,"ssvc_technical_impact":"partial","cwes":["CWE-305"],"nvd_references":["https://www.papercut.com/kb/Main/security-bulletin-27-aug-2026-urgent-security-advisory/"],"vuln_status":"Analyzed","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":"2026-08-28T17:04:04.708404Z","updated_at":"2026-09-16T00:00:38.137528Z"},"effective_severity":"HIGH","badges":["kev","poc","news"],"impact_analysis":[],"cvss_v3_decoded":{"version":"3.1","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":"H","value_label":"High"},{"metric":"A","name":"Availability","value":"H","value_label":"High"}]},"cvss_v4_decoded":{"version":"4.0","metrics":[{"metric":"AV","name":"Attack Vector","value":"N","value_label":"Network"},{"metric":"AC","name":"Attack Complexity","value":"L","value_label":"Low"},{"metric":"AT","name":"Attack Requirements","value":"N","value_label":"None"},{"metric":"PR","name":"Privileges Required","value":"N","value_label":"None"},{"metric":"UI","name":"User Interaction","value":"N","value_label":"None"},{"metric":"VC","name":"Confidentiality (Vulnerable System)","value":"L","value_label":"Low"},{"metric":"VI","name":"Integrity (Vulnerable System)","value":"H","value_label":"High"},{"metric":"VA","name":"Availability (Vulnerable System)","value":"L","value_label":"Low"},{"metric":"SC","name":"Confidentiality (Subsequent System)","value":"N","value_label":"None"},{"metric":"SI","name":"Integrity (Subsequent System)","value":"N","value_label":"None"},{"metric":"SA","name":"Availability (Subsequent System)","value":"N","value_label":"None"}]},"affected":[{"vendor_slug":"papercut","vendor_name":"PaperCut","product_slug":"papercut-mf","product_name":"PaperCut MF","version_start":null,"version_start_inclusive":null,"version_end":"24.1.9","version_end_inclusive":false,"cpe23_uri":"cpe:2.3:a:papercut:papercut_mf:*:*:*:*:*:*:*:*"},{"vendor_slug":"papercut","vendor_name":"PaperCut","product_slug":"papercut-mf-ng","product_name":"PaperCut MF/NG","version_start":"0","version_start_inclusive":true,"version_end":"24.1.10, 25.0.13, 26.0.5","version_end_inclusive":false,"cpe23_uri":"cve5:papercut:papercut-mf-ng:0:24.1.10, 25.0.13, 26.0.5"},{"vendor_slug":"papercut","vendor_name":"PaperCut","product_slug":"papercut-mf-ng","product_name":"PaperCut MF/NG","version_start":"0","version_start_inclusive":true,"version_end":"24.1.10","version_end_inclusive":false,"cpe23_uri":"cve5:papercut:papercut-mf-ng:0:24.1.10"},{"vendor_slug":"papercut","vendor_name":"PaperCut","product_slug":"papercut-mf-ng","product_name":"PaperCut MF/NG","version_start":"25.0.0","version_start_inclusive":true,"version_end":"25.0.13","version_end_inclusive":false,"cpe23_uri":"cve5:papercut:papercut-mf-ng:25.0.0:25.0.13"},{"vendor_slug":"papercut","vendor_name":"PaperCut","product_slug":"papercut-mf-ng","product_name":"PaperCut MF/NG","version_start":"26.0.0","version_start_inclusive":true,"version_end":"26.0.5","version_end_inclusive":false,"cpe23_uri":"cve5:papercut:papercut-mf-ng:26.0.0:26.0.5"},{"vendor_slug":"papercut","vendor_name":"PaperCut","product_slug":"papercut-ng","product_name":"PaperCut NG","version_start":null,"version_start_inclusive":null,"version_end":"24.1.9","version_end_inclusive":false,"cpe23_uri":"cpe:2.3:a:papercut:papercut_ng:*:*:*:*:*:*:*:*"}],"exploit_refs":[{"source":"nuclei","kind":"nuclei","url":"https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2026/CVE-2026-81578.yaml","title":"PaperCut NG/MF <=26.0.4 - Unauthenticated ConfigEditor Access via Tapestry Complex-Direct","author":"darses,DhiyaneshDk","disclosed_at":null}],"news":[{"id":1705,"source":"The Hacker News","url":"https://thehackernews.com/2026/09/attackers-exploit-papercut-flaws-to.html","title":"Attackers Exploit PaperCut Flaws to Steal Credentials From Schools and Universities","summary":"Threat actors are exploiting the newly disclosed PaperCut flaws to facilitate credential theft in attacks targeting the education sector in the U.S. and Europe.\n\nThe Arctic Wolf Adversary Research Team said it observed attackers exploiting CVE-2026-81578 and CVE-2026-82078 – an authentication bypass and remote code execution chain – to conduct command execution and reconnaissance, as well as","thumbnail_url":"https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEguiDwimIl7rewJeRtSYeCkmhBUPSN0lsURwcKXrBtQ4vANRZqEkbjcPBIjODR0kFgIbLqwLiaBcB6lX8M6rilVclrxZcsKogB3NNhnwqJz3dZwgWGZ-6NHnAEGM-ENsEebYhn81lWBN0-nqfYrMLlHoQ3ebfHB7V74NpbKpOZZ84WZYyli7w1lDKJrCtds/s1600/papercut-hacks.jpg","author":"info@thehackernews.com (The Hacker News)","published_at":"2026-09-05T07:31:53Z","fetched_at":"2026-09-05T08:02:30.913800Z","trending_score":0.007106106509109332,"cve_ids":["CVE-2026-81578"]}],"references":[{"url":"https://www.papercut.com/kb/Main/security-bulletin-27-aug-2026-urgent-security-advisory/","source_type":"MISC","tags":[]}],"timeline":[{"type":"published","at":"2026-08-28T11:39:45.402000Z","label":"CVE published","source":null},{"type":"ssvc_changed","at":"2026-08-29T04:49:55.171411Z","label":"SSVC decision revised","source":"vulnrichment"},{"type":"ssvc_changed","at":"2026-08-29T04:49:55.171411Z","label":"SSVC decision revised","source":"vulnrichment"},{"type":"ssvc_changed","at":"2026-08-29T04:49:55.171411Z","label":"SSVC decision revised","source":"vulnrichment"},{"type":"cisa_reported","at":"2026-08-31T00:00:00Z","label":"Added to CISA KEV catalog","source":"kev"},{"type":"ssvc_changed","at":"2026-08-31T13:35:30.379951Z","label":"SSVC decision revised","source":"vulnrichment"},{"type":"ssvc_changed","at":"2026-08-31T17:35:30.378155Z","label":"SSVC decision revised","source":"vulnrichment"},{"type":"cvss_changed","at":"2026-09-03T03:38:56.597934Z","label":"CVSS score revised","source":"nvd"},{"type":"cvss_changed","at":"2026-09-03T03:38:56.597934Z","label":"CVSS score revised","source":"nvd"},{"type":"cvss_changed","at":"2026-09-03T03:38:56.597934Z","label":"CVSS score revised","source":"nvd"},{"type":"first_article","at":"2026-09-05T07:31:53Z","label":"First news coverage","source":"The Hacker News"},{"type":"poc_available","at":"2026-09-16T00:00:08.007433Z","label":"Public PoC available","source":"nuclei"}]}