CVE-2023-27350

PaperCut MF/NG Improper Access Control

9.8 CRITICALActively exploited (CISA KEV)Used in ransomwarePublic exploitEPSS 100.0%

Published20 Apr 2023
Added to CISA KEV21 Apr 2023
Remediation due12 May 2023

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.

CVSS 3.1 breakdown

Attack vectorNetwork

Attack complexityLow

Privileges requiredNone

User interactionNone

ScopeUnchanged

ConfidentialityHigh

IntegrityHigh

AvailabilityHigh

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

Affected products

Papercut Mf≥ 21.0.0 < 21.2.11 · ≥ 22.0.0 < 22.0.9 · ≥ 8.0 < 20.1.7

Papercut Ng≥ 21.0.0 < 21.2.11 · ≥ 22.0.0 < 22.0.9 · ≥ 8.0 < 20.1.7

Remediation

Fixed in

Papercut Mf≥ 21.2.11

Papercut Ng≥ 21.2.11

Patch & vendor advisories

https://www.papercut.com/kb/Main/PO-1216-and-PO-1219

References

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

Related CVEs

Recent high-severity vulnerabilities sharing a weakness type.

Frequently asked

Is CVE-2023-27350 being actively exploited?

Yes. CVE-2023-27350 is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, added 21 Apr 2023. It has been used in ransomware campaigns.

How severe is CVE-2023-27350?

CVE-2023-27350 has a CVSS 3.1 base score of 9.8, rated critical. EPSS estimates a 100.0% probability of exploitation.

Which products are affected by CVE-2023-27350?

Affected products include Papercut Mf, Papercut Ng.

How do I fix CVE-2023-27350?

Upgrade affected software to a fixed version, for example Papercut Mf 21.2.11, Papercut Ng 21.2.11 or later, then confirm no affected versions remain in your inventory.

How Secuno handles this

Secuno correlates vulnerabilities like CVE-2023-27350 against the real software inventory on every managed device, every day. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. Because it is on the CISA KEV list, Secuno flags any affected asset as top-priority automatically. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.

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Data from the NVD, CISA KEV catalog and FIRST EPSS. CVSS 3.1 base score shown where available.