CVE-2026-55467
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.
Does this matter?
Lower severity and a low EPSS score (0.18%). Track it; it rarely justifies an emergency change on its own.
Description
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 3.1
- 2.5 LOWCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L
- EPSS
- 0.18% probability · 8th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-93, CWE-94, CWE-150
- Affected
- openprinting/cups
- Source
- security-advisories@github.com
EPSS moved from 0.2% on 16 October 2026 to 0.2% on 26 October 2026.
References
- https://github.com/OpenPrinting/cups/commit/0cf4e7814d6810ed3c454222bce3aa342d541681Patch
- https://github.com/OpenPrinting/cups/commit/a9e7e7a3a019d0fa063d29409d3f82e4c6d5a008Patch
- https://github.com/OpenPrinting/cups/releases/tag/v2.4.20Release Notes
- https://github.com/OpenPrinting/cups/security/advisories/GHSA-69qc-prxg-h2c7Exploit, Vendor Advisory
- https://github.com/OpenPrinting/cups/security/advisories/GHSA-69qc-prxg-h2c7Exploit, Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.