{"schemaVersion":3,"id":"CVE-2026-106499","aliases":["GHSA-mfvq-x7vr-rgqg"],"status":"published","duplicateOf":null,"title":null,"description":"Backstage is an open framework for building developer portals. Prior to 4.1.0, the @backstage/plugin-scaffolder-backend package could expose secret-derived values in Scaffolder task logs. Deployments that configure sensitive scaffolder.defaultEnvironment.secrets and allow an attacker to create or modify Scaffolder templates are affected. A template author could cause secret-derived values used during template iteration to be persisted and exposed to users who can access the resulting task logs. This issue is fixed in version 4.1.0.","dates":{"published":"2026-10-06T21:25:56.166Z","modified":"2026-10-07T17:46:09.812Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":4.9,"severity":"medium","version":"3.1","versionLabel":"v3.1","source":"CVE.org","vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N","computed":false,"selection":"backend-summary"},"metrics":[{"version":"3.1","versionLabel":"v3.1","source":"CVE.org","score":4.9,"severity":"medium","vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N","exploitability":null,"impact":null,"computed":false},{"version":"3.1","versionLabel":"v3.1","source":"OSV · 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of Sensitive Information into Log File","description":"The product writes sensitive information to a log file.","type":"weakness","status":"Incomplete","abstraction":"Base","likelihoodOfExploit":"Medium","url":"https://cwe.mitre.org/data/definitions/532.html"}],"affected":[{"vendor":"backstage","product":"backstage","name":"backstage","label":"backstage","ecosystem":null,"cpePart":"a","purl":null,"purlType":null,"versions":[{"text":"< 1.54.6","noFixRecorded":false,"fixedIn":null}],"versionsText":"< 1.54.6","eol":null,"hubHref":"/vendor/backstage/backstage"},{"vendor":"@backstage","product":"plugin-scaffolder-backend","name":"plugin-scaffolder-backend","label":"plugin-scaffolder-backend","ecosystem":null,"cpePart":"a","purl":null,"purlType":null,"versions":[{"text":"< 4.1.0","noFixRecorded":false,"fixedIn":null}],"versionsText":"< 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