CVE-2026-81578

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.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://www.papercut.com/kb/Main/security-bulletin-27-aug-2026-urgent-security-advisory/	Patch Vendor Advisory
https://github.com/rapid7/metasploit-framework/pull/21842	Issue Tracking Patch
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-81578	Patch Third Party Advisory US Government Resource

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:papercut:papercut_mf::::::::
	cpe:2.3:a:papercut:papercut_mf::::::::
	cpe:2.3:a:papercut:papercut_mf::::::::
	cpe:2.3:a:papercut:papercut_ng::::::::
	cpe:2.3:a:papercut:papercut_ng::::::::
	cpe:2.3:a:papercut:papercut_ng::::::::

History

No history.

Information

Published : 2026-08-28 16:18

Updated : 2026-09-14 00:16

NVD link : CVE-2026-81578

Mitre link : CVE-2026-81578

CVE.ORG link : CVE-2026-81578

JSON object : View

Products Affected

papercut

papercut_mf
papercut_ng

CWE

CWE-305

Authentication Bypass by Primary Weakness

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Under specific\u00a0conditions, 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."}], "lastModified": "2026-09-14T00:16:56.207", "cisaActionDue": "2026-09-14", "cisaExploitAdd": "2026-08-31", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:papercut:papercut_mf:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "F2AF3AB4-FD10-4DE1-B906-011F45948BD0", "versionEndExcluding": "24.1.9"}, {"criteria": "cpe:2.3:a:papercut:papercut_mf:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "8F6ED0B8-62DC-4CF9-9810-2CCB824FBCA8", "versionEndExcluding": "25.0.12", "versionStartIncluding": "25.0.2"}, {"criteria": "cpe:2.3:a:papercut:papercut_mf:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "51E91B81-E311-4BB9-A753-671F0C59E7F7", "versionEndExcluding": "26.0.4", "versionStartIncluding": "26.0.2"}, {"criteria": "cpe:2.3:a:papercut:papercut_ng:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "44FCDCDE-4126-4F4F-89FC-D44924F45C82", "versionEndExcluding": "24.1.9"}, {"criteria": "cpe:2.3:a:papercut:papercut_ng:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "9E727ABD-0007-424D-AB07-FB7816E43792", "versionEndExcluding": "25.0.12", "versionStartIncluding": "25.0.2"}, {"criteria": "cpe:2.3:a:papercut:papercut_ng:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "3938B71A-CB14-4017-A037-7D5F08DAFB13", "versionEndExcluding": "26.0.4", "versionStartIncluding": "26.0.2"}], "operator": "OR"}]}], "sourceIdentifier": "eb41dac7-0af8-4f84-9f6d-0272772514f4", "cisaRequiredAction": "Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA\u2019s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA\u2019s \u201cForensics Triage Requirements\u201d (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.", "cisaVulnerabilityName": "PaperCut NG/MF Missing Authentication for Critical Function Vulnerability"}