PaperCut is warning that hackers are actively exploiting a vulnerability in all versions of its PaperCut NG and PaperCut MF print management software in zero-day attacks.

The company says it is aware of confirmed attacks on customers and is urging organizations with Internet-exposed PaperCut Application Servers to immediately restrict access to the web interfaces to trusted IP addresses.

“PaperCut Software security response team is investigating active exploitation of a vulnerability affecting PaperCut NG and PaperCut MF,” reads an urgent security advisory published Thursday.