{"schemaVersion":3,"id":"CVE-2026-106492","aliases":["GHSA-cq7v-rfgc-5c7v"],"status":"published","duplicateOf":null,"title":null,"description":"Backstage is an open framework for building developer portals. Prior to 0.16.1 and 0.17.8, the @backstage/backend-defaults package is affected by improper preservation of access restrictions during service credential delegation. An external service credential configured with access restrictions (e.g., read-only) could bypass those restrictions by routing requests through plugin delegation paths. This could allow a restricted service to perform operations beyond its intended scope, including write operations on plugins it was restricted to read-only access for. This issue is fixed in versions 0.16.1 and 0.17.8.","dates":{"published":"2026-10-06T20:48:05.896Z","modified":"2026-10-09T01:51:07.252Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":7.6,"severity":"high","version":"3.1","versionLabel":"v3.1","source":"CVE.org","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:L","computed":false,"selection":"backend-summary"},"metrics":[{"version":"3.1","versionLabel":"v3.1","source":"CVE.org","score":7.6,"severity":"high","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:L","exploitability":null,"impact":null,"computed":false},{"version":"3.1","versionLabel":"v3.1","source":"OSV · 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0.17.8","eol":null,"hubHref":null}],"affectedCount":3,"eol":{"hasEol":false,"count":0},"references":[{"url":"https://github.com/backstage/backstage/security/advisories/GHSA-cq7v-rfgc-5c7v","label":"github.com/backstage/backstage/security/advisories/GHSA-cq7v-rfgc-5c7v","hostname":"github.com","tags":["X Refsource CONFIRM","WEB"]},{"url":"https://github.com/backstage/backstage/commit/40346245c53e1bf26dee56601e95c5c4ab9cc124","label":"github.com/backstage/backstage/commit/40346245c53e1bf26dee56601e95c5c4ab9cc124","hostname":"github.com","tags":["X Refsource MISC","WEB"]},{"url":"https://github.com/backstage/backstage/commit/bc80ffdafbc92ff7b8c72347eace13cb8688fd33","label":"github.com/backstage/backstage/commit/bc80ffdafbc92ff7b8c72347eace13cb8688fd33","hostname":"github.com","tags":["X Refsource MISC","WEB"]},{"url":"https://github.com/backstage/backstage/releases/tag/v1.49.6","label":"github.com/backstage/backstage/releases/tag/v1.49.6","hostname":"github.com","tags":["X Refsource 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