CVE-2026-34990 OpenPrinting CVE debrief

Who should care

Linux and Unix-like operating system users and administrators who use OpenPrinting CUPS versions 2.4.16 and prior should be aware of this vulnerability. They should assess the vulnerability of their installations, implement compensating controls, and monitor for suspicious activity. Users should also plan for vendor-supported updates or mitigations through normal change control.

Technical summary

In OpenPrinting CUPS versions 2.4.16 and prior, a local unprivileged user can coerce cupsd into authenticating to an attacker-controlled localhost IPP service with a reusable Authorization: Local ... token. This token is sufficient to drive /admin/ requests on localhost. An attacker can combine CUPS-Create-Local-Printer with printer-is-shared=true to persist a file:///... queue, despite the normal FileDevice policy rejecting such URIs. This allows for an arbitrary root file overwrite.

Defensive priority

Medium

Recommended defensive actions

• Inventory and assess the vulnerability of OpenPrinting CUPS installations
• Implement compensating controls to limit local unprivileged user access
• Monitor for suspicious activity and implement exception tracking
• Apply patches or updates when available
• Review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up
• Track exceptions, retest remediated assets, and close the item only after evidence is documented

Evidence notes

The CVE record was published on 2026-04-03T22:16:27.400Z and was last modified on 2026-07-24T21:10:00.143Z. The NVD entry is currently Analyzed. This information is based on the NVD entry and CVE record. The vulnerability affects OpenPrinting CUPS versions 2.4.16 and prior. There are no publicly available patches at the time of publication. Evidence limits suggest verifying the affected scope and vendor guidance.

Official resources