{"schemaVersion":3,"id":"CVE-2026-55453","aliases":["UBUNTU-CVE-2026-55453","DEBIAN-CVE-2026-55453"],"status":"published","duplicateOf":null,"title":null,"description":"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.","dates":{"published":"2026-10-15T17:11:21.208Z","modified":"2026-10-16T17:12:58.110Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":3.3,"severity":"low","version":"3.1","versionLabel":"v3.1","source":"CVE.org","vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L","computed":false,"selection":"backend-summary"},"metrics":[{"version":"3.1","versionLabel":"v3.1","source":"CVE.org","score":3.3,"severity":"low","vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L","exploitability":null,"impact":null,"computed":false},{"version":"3.1","versionLabel":"v3.1","source":"NVD","score":3.3,"severity":"low","vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L","exploitability":null,"impact":null,"computed":false},{"version":"3.1","versionLabel":"v3.1","source":"OSV · Debian","score":3.3,"severity":"low","vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L","exploitability":4.6,"impact":2.3,"computed":true},{"version":"3.1","versionLabel":"v3.1","source":"OSV · Ubuntu","score":3.3,"severity":"low","vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L","exploitability":4.6,"impact":2.3,"computed":true}]},"epss":{"probability":0.00181,"percentile":0.07209,"severity":"low","asOf":"2026-10-19T00:00:00.000Z","change":{"pp":null,"baselineDate":null,"baselineScore":null},"history":[{"date":"2026-10-16T00:00:00.000Z","score":0.00181,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.00181,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.00181,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.00181,"percentile":0.07209}],"last30":[{"date":"2026-10-16T00:00:00.000Z","score":0.00181,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.00181,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.00181,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.00181,"percentile":0.07209}]},"kev":{"state":"not-listed","entries":[],"listedCount":0,"totalCatalogs":3,"catalogs":[{"source":"cisa","label":"CISA","listed":false,"entry":null},{"source":"enisa","label":"ENISA","listed":false,"entry":null},{"source":"circl","label":"CIRCL","listed":false,"entry":null}]},"ransomware":{"state":"none-recorded","sources":[]},"exploits":[],"exploitCount":0,"weaknesses":[{"id":"CWE-74","name":"Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')","description":"The product constructs all or part of a command, data structure, or record using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify how it is parsed or interpreted when it is sent to a downstream component.","type":"weakness","status":"Incomplete","abstraction":"Class","likelihoodOfExploit":"High","url":"https://cwe.mitre.org/data/definitions/74.html"},{"id":"CWE-77","name":"Improper Neutralization of Special Elements used in a Command ('Command Injection')","description":"The product constructs all or part of a command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended command when it is sent to a downstream component.","type":"weakness","status":"Draft","abstraction":"Class","likelihoodOfExploit":"High","url":"https://cwe.mitre.org/data/definitions/77.html"},{"id":"CWE-78","name":"Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')","description":"The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component.","type":"weakness","status":"Stable","abstraction":"Base","likelihoodOfExploit":"High","url":"https://cwe.mitre.org/data/definitions/78.html"}],"affected":[{"vendor":"debian","product":"cups","name":"cups","label":"cups","ecosystem":"Debian","cpePart":null,"purl":"pkg:deb/debian/cups","purlType":"deb","versions":[{"text":"All versions","noFixRecorded":true,"fixedIn":null}],"versionsText":"All versions (No fix recorded)","eol":null,"hubHref":null},{"vendor":"ubuntu","product":"cups","name":"cups","label":"cups","ecosystem":"Ubuntu","cpePart":null,"purl":"pkg:deb/ubuntu/cups","purlType":"deb","versions":[{"text":"All versions","noFixRecorded":true,"fixedIn":null}],"versionsText":"All versions (No fix recorded)","eol":null,"hubHref":null},{"vendor":"openprinting","product":"cups","name":"cups","label":"cups","ecosystem":null,"cpePart":"a","purl":null,"purlType":null,"versions":[{"text":"< 2.4.20","noFixRecorded":false,"fixedIn":null}],"versionsText":"< 2.4.20","eol":null,"hubHref":"/vendor/openprinting/cups"}],"affectedCount":3,"eol":{"hasEol":false,"count":0},"references":[{"url":"https://ubuntu.com/security/CVE-2026-55453","label":"ubuntu.com/security/CVE-2026-55453","hostname":"ubuntu.com","tags":["REPORT"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-55453","label":"www.cve.org/CVERecord?id=CVE-2026-55453","hostname":"www.cve.org","tags":["REPORT"]},{"url":"https://github.com/OpenPrinting/cups/security/advisories/GHSA-7hqf-mfhx-7r3v","label":"github.com/OpenPrinting/cups/security/advisories/GHSA-7hqf-mfhx-7r3v","hostname":"github.com","tags":["REPORT","X Refsource CONFIRM"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2026-55453","label":"security-tracker.debian.org/tracker/CVE-2026-55453","hostname":"security-tracker.debian.org","tags":["Advisory"]},{"url":"https://github.com/OpenPrinting/cups/commit/806e1b483096c51d59432468f4afdd7387d81dd7","label":"github.com/OpenPrinting/cups/commit/806e1b483096c51d59432468f4afdd7387d81dd7","hostname":"github.com","tags":["X Refsource MISC"]},{"url":"https://github.com/OpenPrinting/cups/commit/d41cf0616688721e9d435d54118c4c8a36ed596a","label":"github.com/OpenPrinting/cups/commit/d41cf0616688721e9d435d54118c4c8a36ed596a","hostname":"github.com","tags":["X Refsource MISC"]},{"url":"https://github.com/OpenPrinting/cups/releases/tag/v2.4.20","label":"github.com/OpenPrinting/cups/releases/tag/v2.4.20","hostname":"github.com","tags":["X Refsource MISC"]}],"lineage":{"upstream":[],"downstream":["MGASA-2026-0483","RHSA-2026:84421"],"duplicates":[],"related":[]},"timeline":[{"kind":"published","date":"2026-10-15T17:11:21.208Z","label":"Published","detail":"Vulnerability first disclosed.","source":null},{"kind":"modified","date":"2026-10-16T17:12:58.110Z","label":"Last modified","detail":"Vulnerability information updated.","source":null}],"risk":{"score":13,"level":"low","profile":"Default","thresholds":{"critical":75,"high":50,"medium":25,"low":10}},"meta":{"dataAsOf":"2026-10-19T22:25:44.811Z","stale":false,"partial":false}}