Security News > 2023 > August > New PaperCut critical bug exposes unpatched servers to RCE attacks

PaperCut recently fixed a critical security vulnerability in its NG/MF print management software that allows unauthenticated attackers to gain remote code execution on unpatched Windows servers.
While it only impacts servers in non-default configurations where the external device integration setting is toggled, Horizon3 said in a report published on Friday that most Windows PaperCut servers have it enabled.
A Shodan search shows that roughly 1,800 PaperCut servers are currently exposed online, although not all are vulnerable to CVE-2023-39143 attacks.
PaperCut servers were targeted by several ransomware gangs earlier this year by exploiting another critical unauthenticated RCE vulnerability and a high-severity information disclosure flaw.
Microsoft linked the attacks targeting PaperCut servers to the Clop and LockBit ransomware gangs, who used the access to steal corporate data from compromised systems.
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Related Vulnerability
DATE | CVE | VULNERABILITY TITLE | RISK |
---|---|---|---|
2023-08-04 | CVE-2023-39143 | Path Traversal vulnerability in Papercut MF PaperCut NG and PaperCut MF before 22.1.3 on Windows allow path traversal, enabling attackers to upload, read, or delete arbitrary files. | 9.8 |