Known exploited · PaperCut
CVE-2023-27350: PaperCut MF/NG Improper Access Control Vulnerability
What it is
PaperCut MF/NG contains an improper access control vulnerability within the SetupCompleted class that allows authentication bypass and code execution in the context of system.
- Vendor
- PaperCut
- Product
- MF/NG
- Added to KEV
- April 21, 2023
- CISA due date
- May 12, 2023
- Ransomware use
- Known
- Weakness
- CWE-284: Improper Access Control
What CISA requires
Apply updates per vendor instructions.
Forensic triage
No
What to do now
- Find every instance of MF/NG you run, including the forgotten ones, and check its version against the vendor advisory.
- Apply the vendor's fix or mitigation, before May 12, 2023 if you are bound by CISA's deadline, sooner if it faces the internet.
- Assume it was tried against you already: look for signs of exploitation from the date it was added, not from the day you patched.
References
H2 Security
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Start freeSource: CISA Known Exploited Vulnerabilities Catalog (public domain), catalog version 2026.10.01.