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TI-2023-12086 Aliases CVE-2023-27351GHSA-2c69-r2jh-xjvm

Improper authentication in PaperCut NG

Priority CRITICAL 92Exploited in the wildCWE-287Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
High · None · None
Fix status
No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-287.

Summary

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.

Why it matters now

Exploitation Active In CISA KEV since 2026-04-20CISA due date 2026-05-04Known ransomware use
EPSS 0.78052 99th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Active
Automatable
Yes
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
PaperCutNG22.0.5 (Build 63914)—No fix listedCNA
  • NG VendorPaperCut Affected 22.0.5 (Build 63914) Fixed in — No fix listed CNA

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:a:papercut:papercut_mf:*:*:*:*:*:*:*:*15.0 to before 20.1.7; 21.0.0 to before 21.2.11; 22.0.0 to before 22.0.9VulnerablePaperCut
cpe:2.3:a:papercut:papercut_ng:*:*:*:*:*:*:*:*15.0 to before 20.1.7; 21.0.0 to before 21.2.11; 22.0.0 to before 22.0.9VulnerablePaperCut
  • cpe:2.3:a:papercut:papercut_mf:*:*:*:*:*:*:*:* Versions 15.0 to before 20.1.7; 21.0.0 to before 21.2.11; 22.0.0 to before 22.0.9 Vulnerable ·PaperCut
  • cpe:2.3:a:papercut:papercut_ng:*:*:*:*:*:*:*:* Versions 15.0 to before 20.1.7; 21.0.0 to before 21.2.11; 22.0.0 to before 22.0.9 Vulnerable ·PaperCut

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-04-20 Added to CISA KEV
  2. 2026-10-02 Threatist record created from CVE-2023-27351
  3. 2026-10-03 Alias added: GHSA-2c69-r2jh-xjvm

References

Advisory 2

  • TI-2026-56642 PaperCut MF/NG: Unsafe Dynamic Class Loading in Database Connector KEVCVSS 4.0CRITICAL 9.4
  • TI-2023-12085 Improper access control in PaperCut NG KEVCVSS 3.1CRITICAL 9.8
  • TI-2023-02373 PaperCut MF/NG 22.0.10 (Build 65996 2023-03-27) - Remote code execution via CSRF KEVCVSS 3.1HIGH 8.8
  • TI-2026-56284 PaperCut MF/NG: Authentication Bypass KEVCVSS 4.0HIGH 8.8
  • TI-2023-20314 PaperCut NG and PaperCut MF before 22.1.3 on Windows allow path traversal, enabling… CVSS 3.1CRITICAL 9.8
  • TI-2024-01136 Incorrect authorization controls in PaperCut NG/MF APIs CVSS 3.1CRITICAL 9.8
See all 30 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences