CVE-2026-87739: CWE-639 Authorization bypass through User-Controlled key in PaperCut PaperCut NG/MF
CVE-2026-87739 is an improper authentication vulnerability in PaperCut NG/MF that allows unauthenticated remote attackers to generate reports without valid credentials. This can lead to unauthorized access to sensitive information contained in those reports. The vulnerability affects versions from 0 up to but not including 25.0.13, and versions from 26.0.0 up to but not including 26.0.5. The severity is rated medium with a CVSS 4.0 base score of 6.9.
AI Analysis
Technical Summary
An authorization bypass vulnerability (CWE-639) exists in PaperCut NG/MF where an unauthenticated remote attacker can submit report generation requests without valid credentials. This improper authentication flaw allows the attacker to trigger report generation and access sensitive information contained within those reports. The vulnerability affects PaperCut NG/MF versions >=0 <25.0.13 and >=26.0.0 <26.0.5. No known exploits are reported in the wild, and no vendor patch links are provided in the input data.
Potential Impact
An attacker can remotely generate reports without authentication, leading to unauthorized disclosure of sensitive information. This compromises confidentiality but does not indicate impact on integrity or availability. The medium severity score reflects the potential information exposure risk.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Since no patch links are provided, users should monitor PaperCut's official advisories for updates. Until a fix is available, restrict network access to the PaperCut NG/MF report generation interface to trusted users only.
CVE-2026-87739: CWE-639 Authorization bypass through User-Controlled key in PaperCut PaperCut NG/MF
Description
CVE-2026-87739 is an improper authentication vulnerability in PaperCut NG/MF that allows unauthenticated remote attackers to generate reports without valid credentials. This can lead to unauthorized access to sensitive information contained in those reports. The vulnerability affects versions from 0 up to but not including 25.0.13, and versions from 26.0.0 up to but not including 26.0.5. The severity is rated medium with a CVSS 4.0 base score of 6.9.
CVSS v4.0
Score 6.9medium
Affected software
PaperCut
PaperCut NG/MF
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
An authorization bypass vulnerability (CWE-639) exists in PaperCut NG/MF where an unauthenticated remote attacker can submit report generation requests without valid credentials. This improper authentication flaw allows the attacker to trigger report generation and access sensitive information contained within those reports. The vulnerability affects PaperCut NG/MF versions >=0 <25.0.13 and >=26.0.0 <26.0.5. No known exploits are reported in the wild, and no vendor patch links are provided in the input data.
Potential Impact
An attacker can remotely generate reports without authentication, leading to unauthorized disclosure of sensitive information. This compromises confidentiality but does not indicate impact on integrity or availability. The medium severity score reflects the potential information exposure risk.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Since no patch links are provided, users should monitor PaperCut's official advisories for updates. Until a fix is available, restrict network access to the PaperCut NG/MF report generation interface to trusted users only.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- PaperCut
- Date Reserved
- 2026-09-09T04:24:33.190Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6ab4cb33f7a7c54106ffdfdd
Added to database: 09/24/2026, 07:03:15 UTC
Last enriched: 09/24/2026, 07:17:45 UTC
Last updated: 09/24/2026, 09:22:28 UTC
Views: 20
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