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
papercut: papercut mf; papercut: papercut ng
References1
- www.papercut.com/kb/Main/papercut-ng-mf-and-papercut-hive-secur… Vendor Advisory
Metrics
- CVSS 3.1
-
8.1
HIGH
Score source: NVD
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H - CVSS 4.0
-
4.1
MEDIUM
Score source: CNA
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 28 · as of 13 November 2026
- CWE
- CWE-20CWE-367
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