{"id":"CVE-2026-106499","aliases":["EUVD-2026-94057","GHSA-mfvq-x7vr-rgqg"],"status":"published","title":"Backstage: Secret-derived values may be exposed in scaffolder task logs","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.","severity":{"version":"3.1","score":4.9,"vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.0027,"percentile":0.19353,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-532"],"published":"2026-10-06T21:25:56Z","modified":"2026-10-28T02:31:02Z","fixes":[{"ecosystem":"npm","package":"@backstage/plugin-scaffolder-backend","fixed_in":["4.1.0"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"npm","package":"@backstage/plugin-scaffolder-backend","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"4.1.0"}]}]},{"source":"osv","ecosystem":"npm","package":"@backstage/plugin-scaffolder-backend","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"4.1.0"}]}]}],"products":[{"vendor":"@backstage","product":"plugin-scaffolder-backend"},{"vendor":"backstage","product":"backstage"},{"vendor":"linuxfoundation","product":"backstage"},{"vendor":"linuxfoundation","product":"backstage\\/plugin-scaffolder-backend"}],"references":[{"url":"https://github.com/backstage/backstage/security/advisories/GHSA-mfvq-x7vr-rgqg","tags":["x_refsource_CONFIRM","Mitigation","Vendor Advisory","advisory","web"]},{"url":"https://github.com/backstage/backstage/commit/dc30fae2d96cb1606d36cc40b242f9b9e539bd70","tags":["x_refsource_MISC","Patch","fix","web"]},{"url":"https://github.com/backstage/backstage/releases/tag/v1.54.6","tags":["x_refsource_MISC","Patch","Release Notes","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-106499","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-mfvq-x7vr-rgqg"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/106xxx/CVE-2026-106499.json","tags":["advisory"]},{"url":"https://github.com/backstage/backstage","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2026-106499","title":"Backstage: Secret-derived values may be exposed in scaffolder task logs","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.","status":"published","published":"2026-10-06T21:25:56.166Z","modified":"2026-10-07T17:46:09.812Z","cvss":[{"version":"3.1","score":4.9,"vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N","level":"medium","assessor":"cna"}],"cwes":["CWE-532"],"updated_at":"2026-11-02T14:20:04.156238Z"}],"euvd":[{"id":"EUVD-2026-94057","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.","status":"published","published":"2026-10-06T21:25:56Z","modified":"2026-10-07T17:46:09Z","cvss":[{"version":"3.1","score":4.9,"vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N","level":"medium"}],"updated_at":"2026-11-02T17:27:34.815018Z"}],"ghsa":[{"id":"GHSA-mfvq-x7vr-rgqg","title":"Backstage: Secret-derived values may be exposed in scaffolder task logs","description":"### Impact\n\nDeployments 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 in task logs, exposing those values to users with access to the resulting task logs.\n\n### Patches\n\nPatched in `@backstage/plugin-scaffolder-backend` version `4.1.0`\n\n### Workarounds\n\n- Restrict permission to create or update Template entities to fully trusted parties, as recommended by the Backstage threat model.\n- If that restriction cannot be guaranteed, remove sensitive values from `scaffolder.defaultEnvironment.secrets` until a patched version is available.\n\nNo complete workaround is known that preserves both untrusted template authoring and access to sensitive default-environment secrets.","status":"published","published":"2026-10-07T17:59:14Z","modified":"2026-10-07T17:59:15Z","cvss":[{"version":"3.1","score":4.9,"vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N","level":"medium"}],"cwes":["CWE-532"],"updated_at":"2026-11-02T14:41:28.013673Z"}],"nvd":[{"id":"CVE-2026-106499","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.","status":"published","published":"2026-10-06T22:17:04.907Z","modified":"2026-10-15T02:16:07.97Z","cvss":[{"version":"3.1","score":4.9,"vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N","level":"medium","assessor":"secondary"}],"cwes":["CWE-532"],"updated_at":"2026-11-02T14:12:54.809359Z"}],"osv":[{"id":"CVE-2026-106499","title":"Backstage: Secret-derived values may be exposed in scaffolder task logs","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.","status":"published","published":"2026-10-06T21:25:56.166Z","modified":"2026-10-28T02:31:02.629502105Z","cvss":[{"version":"3.1","score":4.9,"vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N","level":"medium"}],"cwes":["CWE-532"],"updated_at":"2026-11-02T15:44:54.583213Z"},{"id":"GHSA-mfvq-x7vr-rgqg","title":"Backstage: Secret-derived values may be exposed in scaffolder task logs","description":"### Impact\n\nDeployments 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 in task logs, exposing those values to users with access to the resulting task logs.\n\n### Patches\n\nPatched in `@backstage/plugin-scaffolder-backend` version `4.1.0`\n\n### Workarounds\n\n- Restrict permission to create or update Template entities to fully trusted parties, as recommended by the Backstage threat model.\n- If that restriction cannot be guaranteed, remove sensitive values from `scaffolder.defaultEnvironment.secrets` until a patched version is available.\n\nNo complete workaround is known that preserves both untrusted template authoring and access to sensitive default-environment secrets.","status":"published","published":"2026-10-07T17:59:14Z","modified":"2026-10-07T18:15:10.788059211Z","cvss":[{"version":"3.1","score":4.9,"vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N","level":"medium"}],"cwes":["CWE-532"],"updated_at":"2026-11-02T15:46:51.811331Z"}]}}