CVE-2026-55467: openprinting cups

CVSS 2.5 (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 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.

Affected products (NVD): openprinting cups

Fixed in (NVD): 2.4.20

Weakness: CWE-93, CWE-94, CWE-150

Source: NVD CVE-2026-55467

References

• https://github.com/OpenPrinting/cups/commit/0cf4e7814d6810ed3c454222bce3aa342d541681
• https://github.com/OpenPrinting/cups/commit/a9e7e7a3a019d0fa063d29409d3f82e4c6d5a008
• https://github.com/OpenPrinting/cups/releases/tag/v2.4.20
• https://github.com/OpenPrinting/cups/security/advisories/GHSA-69qc-prxg-h2c7
• https://github.com/OpenPrinting/cups/security/advisories/GHSA-69qc-prxg-h2c7

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