Bug 2553616 (CVE-2026-55453)

Summary: CVE-2026-55453 cups: cups: Arbitrary code execution via newline injection in printer status messages
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: unspecifiedKeywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in CUPS. A remote attacker controlling a network printer can achieve arbitrary code execution by returning crafted printer status messages containing newline characters. The CUPS Internet Printing Protocol (IPP) backend fails to sanitize line breaks in status attributes, allowing injected control directives to be processed by the printing scheduler. These injected directives modify local printer configuration files, causing subsequent print jobs to execute arbitrary commands with the privileges of the print service account.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-10-15 17:25:19 UTC 
OpenPrinting CUPS is an open source printing system for Linux and other Unix-like operating systems. Prior to 2.4.20, the backend/ipp.c quote_string() function preserves carriage-return and line-feed characters in a remote printer-controlled marker-message before report_attr() writes the value to the scheduler status stream. The scheduler can parse an injected newline as a separate PPD: control line and persist an attacker-selected PPD keyword. The reporter demonstrated that a later print job on a Foomatic-backed queue could consume an injected FoomaticRIPCommandLine value and execute in the filter context as lp. This issue is fixed in version 2.4.20.