How severe is CVE-2023-27351?

CVE-2023-27351 has a CVSS 3.0 base score of 8.2 (HIGH). EPSS estimates a 78.1% probability of exploitation in the next 30 days. It is listed in the CISA Known Exploited Vulnerabilities catalog.

CVE-2023-27351: PaperCut NG/MF Improper Authentication

CISA Known Exploited Vulnerabilities

PaperCut NG/MF Improper Authentication Vulnerability is confirmed as actively exploited and is listed in the CISA KEV catalog.

Added to KEV

2026-04-20

Remediation due

2026-05-04

Ransomware

Known use

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.

CISA notes
https://www.papercut.com/kb/Main/PO-1216-and-PO-1219 ; https://nvd.nist.gov/vuln/detail/CVE-2023-27351

Description

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.

Severity

CVSS 3.0 · CNA8.2 HIGH

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N

SSVC · CISA-ADP

Exploitationactive

Automatableyes

Technical impacttotal

Affected Products

Vendor	Product	Affected versions
PaperCut	NG	22.0.5 (Build 63914)

References

2 Links

Other references

Record Details

Published

2023-04-20

Last updated

2026-10-01

Assigner (CNA)

zdi

Credited to

Piotr Bazydlo (@chudypb) of Trend Micro Zero Day Initiative

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PaperCut MF/NG: Unsafe Dynamic Class Loading in Database Connector

CVE-2023-25338.4

PaperCut MF/NG 22.0.10 (Build 65996 2023-03-27) - Remote code execution via CSRF

Related Tool Categories

Tool categories that test for or protect against this vulnerability class.

CWE-287 · Improper Authentication

IAM Tools Application Security Tools

CVE record data © The MITRE Corporation, used under the CVE Terms of Use. Exploited-in-the-wild data from the CISA Known Exploited Vulnerabilities catalog (CC0). Exploit prediction scores by FIRST EPSS (first.org/epss). This site is not endorsed or certified by MITRE, NVD, CISA, or FIRST.