CVE-2026-55453: openprinting cups

CVSS 3.3 (low) · published 2026-10-15

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.

Affected products (NVD): openprinting cups

Fixed in (NVD): 2.4.20

Weakness: CWE-74, CWE-77, CWE-78

Source: NVD CVE-2026-55453

References

• https://github.com/OpenPrinting/cups/commit/806e1b483096c51d59432468f4afdd7387d81dd7
• https://github.com/OpenPrinting/cups/commit/d41cf0616688721e9d435d54118c4c8a36ed596a
• https://github.com/OpenPrinting/cups/releases/tag/v2.4.20
• https://github.com/OpenPrinting/cups/security/advisories/GHSA-7hqf-mfhx-7r3v

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