PaperCut, a developer of print management software, has warned customers of two high and critical severity flaws in its MF/NG software versions 8.0 or later on all OS platforms for both application and site servers. The vulnerabilities are being actively exploited by hackers, according to an updated March 2023 security bulletin from the company.
The flaws are an unauthenticated remote code execution flaw, ZDI-CAN-18987/PO-1216, and an unauthenticated information disclosure flaw, ZDI-CAN-19226/PO-1219. The advisory warns that unpatched servers are being exploited in the wild, and recommends upgrading to PaperCut MF and PaperCut NG versions 20.1.7, 21.2.11, and 22.0.9 or later.
PaperCut’s software is compatible with all major brands and platforms, and serves hundreds of millions of people across more than 100 countries, including large companies, state organizations, and education institutes.
While the company has no mitigation for the first flaw, the second can be mitigated by applying “Allow list” restrictions under “Options > Advanced > Security > Allowed site server IP addresses”.
Versions older than 19 are no longer supported, so PaperCut recommends companies purchase an updated license if they use an older, unsupported version.
Administrators who suspect their servers have been compromised should look for suspicious activity in Logs > Application Log within the PaperCut admin interface, and check for new users being created or configuration keys being tampered with.
If the server logs are in debug mode, they should also check for lines mentioning SetupCompleted at a time not correlating with the server installation or upgrade. However, it’s possible that attackers removed traces of their activities from logs, so PaperCut advises admins who suspect a breach to take backups, wipe the Application Server, and rebuild everything from a safe backup point.
Trend Micro informed PaperCut of the two flaws on January 10th, 2023, and will disclose more information about the flaws on May 10th, 2023, to give impacted organizations enough time to apply the security updates. As a precaution, PaperCut has not revealed too much about these vulnerabilities.
