CVE-2023-27351

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.

CVSS 3.1

7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

EPSS

78% chance of exploitation in the next 30 days; higher than 99% of CVEs (scores of 2026-10-25)

CISA KEV

listed 2026-04-20, due 2026-05-04, known ransomware use

CWE

CWE-287

Published

2023-04-20

Modified

2026-10-01

Record from

the NVD, synced 2026-10-19

Affected

• papercut:papercut_mf
• papercut:papercut_ng

References

• https://www.papercut.com/kb/Main/PO-1216-and-PO-1219
• https://www.zerodayinitiative.com/advisories/ZDI-23-232/
• https://www.papercut.com/kb/Main/PO-1216-and-PO-1219
• https://www.zerodayinitiative.com/advisories/ZDI-23-232/
• https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-27351

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