Vulnerability · Published May 5, 2026 · Assigned by PaperCut
CVE-2026-6180PaperCut MF: Card truncation on HP readers
Medium 4.1
In plain English
A medium-severity improper input validation in PaperCut NG/MF from PaperCut. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 27% of all known vulnerabilities).
Official description
A race condition exists in PaperCut MF when processing badge-swipe data from certain HP multifunction devices. Under specific network conditions involving dropped packets and out-of-order sequence counters, the server may incorrectly process fragmented data chunks. If a sequence reset notification fails to reach the server, the server may reject the initial data chunk while erroneously accepting subsequent chunks before a connection reset completes. This leads to the registration of a truncated badge ID string. While this typically results in an authentication failure, the vulnerability is compounded in environments utilizing custom badge-ID post-processing scripts. In such configurations, the truncated string may be transformed into a valid ID belonging to a different user, leading to unauthorized session establishment (Incorrect User Login) on the device.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| PaperCut | PaperCut NG/MF | 0 – before 24.1.90 – before 25.0.10 |
Weakness: CWE-367, CWE-20 · Vector: CVSS:4.0/AV:P/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:L/SI:L/SA:N