CVE-2026-55467

CVE-2026-55467 · CUPS fax option values bypass the CVE-2026-34980 control-character sanitizer (incomplete fix)

This page contains facts from public vulnerability sources. Check the original advisory before updating.

OpenPrinting CUPS is an open source printing system for Linux and other Unix-like operating systems. Prior to 2.4.20, the cupsdCreateJob option-string builder in scheduler/job.c maps attacker-controlled destination-uri and pre-dial-string values from a configured fax queue to the phone and faxPrefix options. Unlike ordinary IPP job attributes, these mapped fax values bypass the control-character sanitizer and are copied directly into the filter options argument. A user permitted to submit a job can therefore inject control characters into the downstream option stream. The reporter states that a downstream fax filter passing these values to a shell or modem command could execute code as lp, while the maintainer states that CUPS has no confidentiality or integrity impact because the only known code-executing filter is optional Foomatic and addressed separately, leaving possible disruption of the affected queue. This issue is fixed in version 2.4.20.

CVSS 2.5 · Low · EPSS 0.2%

Published

2026-10-15T17:08:24.374Z

Updated

2026-10-15T17:49:26.673Z

Stack: system

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