CVE-2023-27350

CVE-2023-27350 is a critical-severity vulnerability in Papercut Papercut Mf with a CVSS 3.x base score of 9.8. It is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, confirming it has been exploited in the wild (added 2023-04-21). The underlying weakness is classified as CWE-284.

Key facts

• Severity: Critical (CVSS 3.x base score 9.8)
• EPSS exploit prediction: 100% (100th percentile)
• Actively exploited: Yes — listed in CISA KEV (added 2023-04-21)
• EU (EUVD) id: EUVD-2023-31126
• EU exploitation: Flagged exploited in the ENISA EU Vulnerability Database (since 2023-04-21)
• Weakness: CWE-284
• Affected product: Papercut Papercut Mf
• Published: 2023-04-20
• Last modified: 2026-06-17

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 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.

Frequently asked questions

What is 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.

How severe is CVE-2023-27350?

CVE-2023-27350 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2023-27350 being actively exploited?

Yes. CVE-2023-27350 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2023-04-21, which means active exploitation has been confirmed. It should be prioritised for remediation.

What products are affected by CVE-2023-27350?

CVE-2023-27350 primarily affects Papercut Papercut Mf. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-27350?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.

Does CVE-2023-27350 have an EU (EUVD) identifier?

Yes. CVE-2023-27350 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2023-31126. It is also flagged as exploited in the EUVD (since 2023-04-21).

When was CVE-2023-27350 published?

CVE-2023-27350 was published on 2023-04-20 and last updated on 2026-06-17.

References

• http://packetstormsecurity.com/files/171982/PaperCut-MF-NG-Authentication-Bypass-Remote-Code-Execution.html
• http://packetstormsecurity.com/files/172022/PaperCut-NG-MG-22.0.4-Authentication-Bypass.html
• http://packetstormsecurity.com/files/172512/PaperCut-NG-MG-22.0.4-Remote-Code-Execution.html
• http://packetstormsecurity.com/files/172780/PaperCut-PaperCutNG-Authentication-Bypass.html
• https://news.sophos.com/en-us/2023/04/27/increased-exploitation-of-papercut-drawing-blood-around-the-internet/
• https://www.papercut.com/kb/Main/PO-1216-and-PO-1219
• https://www.zerodayinitiative.com/advisories/ZDI-23-233/
• https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-27350

Affected products (2)

• cpe:2.3:a:papercut:papercut_mf:*:*:*:*:*:*:*:*
• cpe:2.3:a:papercut:papercut_ng:*:*:*:*:*:*:*:*

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