CVE-2026-106506
Backstage: Improper input validation in scaffolder task list ordering
Backstage is an open framework for building developer portals. Prior to 4.1.0, the @backstage/plugin-scaffolder-backend package is affected by improper input validation in scaffolder task list ordering. An authenticated Backstage user with permission to create and read relevant scaffolder tasks may be able to infer confidential task data under specific conditions. Successful exploitation requires retained task secrets, visibility of a target task, knowledge of the secret structure, and repeated requests. This issue is fixed in version 4.1.0.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- None
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
5.3
Backstage: Improper input validation in scaffolder task list ordering
Backstage is an open framework for building developer portals. Prior to 4.1.0, the @backstage/plugin-scaffolder-backend package is affected by improper input validation in scaffolder task list ordering. An authenticated Backstage user with permission to create and read relevant scaffolder tasks may be able to infer confidential task data under specific conditions. Successful exploitation requires retained task secrets, visibility of a target task, knowledge of the secret structure, and repeated requests. This issue is fixed in version 4.1.0.
- Record
CVE-2026-106506- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-202, CWE-203
- Updated
- 2026-11-02
EUVDEUVD-2026-94071
5.3
Backstage is an open framework for building developer portals. Prior to 4.1.0, the @backstage/plugin-scaffolder-backend package is affected by improper input validation in scaffolder task list ordering. An authenticated Backstage user with permission to create and read relevant scaffolder tasks may be able to infer confidential task data under specific conditions. Successful exploitation requires retained task secrets, visibility of a target task, knowledge of the secret structure, and repeated requests. This issue is fixed in version 4.1.0.
- Record
EUVD-2026-94071- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-vwp5-f99x-x3rq
5.3
Backstage has improper input validation in scaffolder task list ordering
Impact
An authenticated Backstage user with permission to create and read relevant scaffolder tasks may be able to infer confidential task data under specific conditions. Successful exploitation requires retained task secrets, visibility of a target task, knowledge of the secret structure, and repeated requests.
Patches
Patched in @backstage/plugin-scaffolder-backend version 4.1.0
Workarounds
- At the gateway or reverse proxy, reject task-list requests that specify custom ordering, or allow ordering only by
created_at,status, andcreated_by. - Restrict scaffolder task creation and task read permissions to trusted users, preferably using owner-based task-read conditions.
- Disabling task recovery can reduce secret retention after a task is claimed, but it does not protect secrets in queued tasks and should not be treated as complete mitigation.
- Record
GHSA-vwp5-f99x-x3rq- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-202, CWE-203
- Updated
- 2026-11-02
NVD
5.3
Backstage is an open framework for building developer portals. Prior to 4.1.0, the @backstage/plugin-scaffolder-backend package is affected by improper input validation in scaffolder task list ordering. An authenticated Backstage user with permission to create and read relevant scaffolder tasks may be able to infer confidential task data under specific conditions. Successful exploitation requires retained task secrets, visibility of a target task, knowledge of the secret structure, and repeated requests. This issue is fixed in version 4.1.0.
- Record
CVE-2026-106506- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-202, CWE-203
- Updated
- 2026-11-02
OSV
5.3
Backstage: Improper input validation in scaffolder task list ordering
Backstage is an open framework for building developer portals. Prior to 4.1.0, the @backstage/plugin-scaffolder-backend package is affected by improper input validation in scaffolder task list ordering. An authenticated Backstage user with permission to create and read relevant scaffolder tasks may be able to infer confidential task data under specific conditions. Successful exploitation requires retained task secrets, visibility of a target task, knowledge of the secret structure, and repeated requests. This issue is fixed in version 4.1.0.
- Record
CVE-2026-106506- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-202, CWE-203
- Updated
- 2026-11-02
OSVGHSA-vwp5-f99x-x3rq
5.3
Backstage has improper input validation in scaffolder task list ordering
Impact
An authenticated Backstage user with permission to create and read relevant scaffolder tasks may be able to infer confidential task data under specific conditions. Successful exploitation requires retained task secrets, visibility of a target task, knowledge of the secret structure, and repeated requests.
Patches
Patched in @backstage/plugin-scaffolder-backend version 4.1.0
Workarounds
- At the gateway or reverse proxy, reject task-list requests that specify custom ordering, or allow ordering only by
created_at,status, andcreated_by. - Restrict scaffolder task creation and task read permissions to trusted users, preferably using owner-based task-read conditions.
- Disabling task recovery can reduce secret retention after a task is claimed, but it does not protect secrets in queued tasks and should not be treated as complete mitigation.
- Record
GHSA-vwp5-f99x-x3rq- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-202, CWE-203
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
@backstage/plugin-scaffolder-backendnpm |
before 4.1.0 | 4.1.0 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-106506 is a medium vulnerability (CVSS 5.3) in @backstage Plugin-scaffolder-backend, published October 6, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.22%, the 12th percentile. Fixed in @backstage/plugin-scaffolder-backend 4.1.0.
References
github.com/backstage/backstage/security/advisories/GHSA-vwp5-f99x-x3rq
github.com/backstage/backstage/commit/e673a869449874a9169e8f89852e75e862011b93
github.com/backstage/backstage/releases/tag/v1.54.6
nvd.nist.gov/vuln/detail/CVE-2026-106506
github.com/advisories/GHSA-vwp5-f99x-x3rq
github.com/CVEProject/cvelistV5/tree/main/cves/2026/106xxx/CVE-2026-106506.json
github.com/backstage/backstage