Actively exploited in the wild
PaperCut NG/MF Improper Authentication Vulnerability
PaperCut - NG/MF · Listed in the CISA KEV since 2026-04-20. This indicates confirmed attacks in production environments.
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.
CVE-2023-27351
HighCVSS 7.5KEVSummary
Ta podatność pozwala zdalnym atakującym na ominięcie uwierzytelnienia w dotkniętych instalacjach PaperCut NG w wersji 22.0.5 (Build 63914). Problem wynika z niewłaściwej implementacji algorytmu uwierzytelniania w klasie SecurityRequestFilter.
Risk Assessment
Atakujący mogą wykorzystać tę podatność do uzyskania dostępu do systemu bez konieczności uwierzytelnienia, co stwarza poważne zagrożenie dla bezpieczeństwa organizacji.
Recommendation
Zaleca się aktualizację do najnowszej wersji PaperCut NG, aby usunąć tę podatność oraz wdrożenie dodatkowych środków zabezpieczających w celu ochrony systemu.
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Original NVD description (English source)
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.