What is CVE-2023-27350?

CVE-2023-27350 is a critical-severity vulnerability in Papercut Ng, classified under Improper Access Control. CVSS score: 9.8/10. Published 2023-04-20.

How severe is CVE-2023-27350?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Is CVE-2023-27350 known to be exploited?

Yes. CVE-2023-27350 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2023-04-21), indicating it is being actively exploited. 72 public proof-of-concept repositories are indexed.

Vulnerability in Papercut Ng

CVE-2023-27350

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 SetupCompleted class. The issue results from improper access control. An attacker can leverage this vulnerability to bypass authentication and execute arbitrary code in the context of SYSTEM. Was ZDI-CAN-18987.

Published 2023-04-20 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 1.000 (100.0th percentile), scored 2026-08-30.

Very high probability of exploitation in the next 30 days — among the top 0.1% most-likely-to-be-exploited CVEs. 100th percentile — 100.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

The 30-day trend appears once there are two daily scores.

Affected products

Papercut Ng — versions 22.0.5 (Build 63914)
Papercut Mf
Papercut Ng

Weakness classification (CWE)

CWE-284 — Improper Access Control

CISA KEV (Known Exploited Vulnerabilities)

This CVE is on the CISA KEV catalog, added on 2023-04-21. CISA KEV inclusion means CISA has confirmed in-the-wild exploitation; US federal agencies are required to remediate within a published due date.

BOD 22-01 due date: 2023-05-12.

Required action: Apply updates per vendor instructions.

Known ransomware campaign use: yes.

Public proof-of-concept exploits

References

www.zerodayinitiative.com/advisories/ZDI-23-233/ (VDB Entry, Third Party Advisory)
www.papercut.com/kb/Main/PO-1216-and-PO-1219 (Vendor Advisory)
packetstormsecurity.com/files/171982/PaperCut-MF-NG-Authentication-Bypass-Remot… (VDB Entry, Third Party Advisory)
packetstormsecurity.com/files/172022/PaperCut-NG-MG-22.0.4-Authentication-Bypas… (Exploit, VDB Entry, Third Party Advisory)
news.sophos.com/en-us/2023/04/27/increased-exploitation-of-papercut-drawing-blo… (Third Party Advisory)
packetstormsecurity.com/files/172512/PaperCut-NG-MG-22.0.4-Remote-Code-Executio… (Exploit, VDB Entry, Third Party Advisory)
packetstormsecurity.com/files/172780/PaperCut-PaperCutNG-Authentication-Bypass… (Exploit, VDB Entry, Third Party Advisory)
134c704f-9b21-4f2e-91b3-4a467353bcc0 (US Government Resource)

Frequently asked questions

What is CVE-2023-27350?: CVE-2023-27350 is a critical-severity vulnerability in Papercut Ng, classified under Improper Access Control. CVSS score: 9.8/10. Published 2023-04-20.
How severe is CVE-2023-27350?: Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2023-27350 known to be exploited?: Yes. CVE-2023-27350 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2023-04-21), indicating it is being actively exploited. 72 public proof-of-concept repositories are indexed.