Executive brief
A flaw in the libcupsfilters library, which is used by Linux systems to manage printing tasks, can allow an attacker to disable printing services. By broadcasting a malicious printer advertisement on a local network, an attacker can cause the system's processor to become stuck in an infinite loop. This results in a denial-of-service condition where the printing service becomes unresponsive and system performance is significantly degraded.
Technical details
A vulnerability exists in the cfIEEE1284NormalizeMakeModel() function within cupsfilters/ieee1284.c of libcupsfilters through version 2.1.1. When the function processes an IEEE-1284 device ID containing an empty model (MDL) field, a logic error in the deduplication loop causes it to enter an infinite loop. Specifically, the loop fails to make progress when modelptr equals the buffer, leading to sustained 100% CPU utilization on the affected core. This is reachable over the network via cups-browsed when it processes printer-advertised device IDs via IPP or DNS-SD. At the time of reporting, no upstream fix was available.
Affected products
- OpenPrinting libcupsfilters through 2.1.1
- OpenPrinting cups-filters
- Red Hat Red Hat Enterprise Linux 7
- Red Hat Red Hat Enterprise Linux 8
- Red Hat Red Hat Enterprise Linux 9
- Red Hat Red Hat Enterprise Linux 10
Timeline
- 2026-07-20: other: Reported to Red Hat Bugzilla
- 2026-07-23: advisory: NVD publication date