GHSA-vwp5-f99x-x3rq CVE-2026-106506
Backstage has improper input validation in scaffolder task list ordering
- Severity
- 5.3 / 10
- Medium · CVSS 3.1
- Exploit chance (EPSS)
- 0.22%
- Chance of exploitation in the next 30 days. Higher than 12.28% of scored vulnerabilities.
- Known exploited
- No
- Not in CISA's catalog
- Weakness
- CWE-202 Exposure of Sensitive Information Through Data Queries
- CWE-203 Observable Discrepancy
- Fix
4.1.0- Upgrade @backstage/plugin-scaffolder-backend to this version or later
Description
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.
Affected versions
npm
| Package | Vulnerable | Fixed in |
|---|---|---|
| @backstage/plugin-scaffolder-backend | < 4.1.0 |
4.1.0 |
How to fix
Move to the fixed version or later with your package manager, update the lockfile, and run your tests. If the package only arrives through another dependency, upgrade that dependency first. If none of its releases pulls a fixed version yet, force the version with your package manager's override.
@backstage/plugin-scaffolder-backend npm → 4.1.0
- npm
npm install @backstage/plugin-scaffolder-backend@4.1.0- yarn
yarn add @backstage/plugin-scaffolder-backend@4.1.0- pnpm
pnpm add @backstage/plugin-scaffolder-backend@4.1.0
Severity breakdown
CVSS 3.1 5.3
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N
- Attack vector
- Network
- Attack complexity
- High
- Privileges required
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- None
- Availability
- None
Weakness
CWE-202: Exposure of Sensitive Information Through Data Queries
When trying to keep information confidential, an attacker can often infer some of the information by using statistics.
How to prevent it
- Architecture and Design: This is a complex topic. See the [REF-1492] for a good discussion of best practices.
CWE-203: Observable Discrepancy
The product behaves differently or sends different responses under different circumstances in a way that is observable to an unauthorized actor.
How to prevent it
- Architecture and Design: Compartmentalize the system to have "safe" areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area. Ensure that appropriate compartmentalization is built into the system design, and the compartmentalization allows for and reinforces privilege separation functionality. Architects and designers should rely on the principle of least privilege to decide the appropriate time to use privileges and the time to drop privileges.
- Implementation: Ensure that error messages only contain minimal details that are useful to the intended audience and no one else. The messages need to strike the balance between being too cryptic (which can confuse users) or being too detailed (which may reveal more than intended). The messages should not reveal the methods that were used to determine the error. Attackers can use detailed information to refine or optimize their original attack, thereby increasing their chances of success. If errors must be captured in some detail, record them in log messages, but consider what could occur if the log messages can be viewed by attackers. Highly sensitive information such as passwords should never be saved to log files. Avoid inconsistent messaging that might accidentally tip off an attacker about internal state, such as whether a user account exists or not.
References
Advisories
Packages
Other links
Timeline
- Published
- Last updated by the source
- Latest EPSS score
Related advisories
| Advisory | Severity | Why it's related |
|---|---|---|
| GHSA-4xvq-3m68-h444 Backstage has sensitive information exposure in scaffolder task logs | Medium | Also affects @backstage/plugin-scaffolder-backend |
| GHSA-hmp2-4m7g-22cv Backstage: Scaffolder action input authorization bypass | High | Also affects @backstage/plugin-scaffolder-backend |
| GHSA-95p4-vv4g-jxxm Backstage may expose sensitive information in Scaffolder task failure events | Medium | Also affects @backstage/plugin-scaffolder-backend |
| GHSA-g2v8-7jhw-pp8p Backstage: Sensitive information exposure in Scaffolder | Critical | Also affects @backstage/plugin-scaffolder-backend |
| GHSA-xvgh-hmx8-9xxf Backstage: Improper task state validation in Scaffolder backend | High | Also affects @backstage/plugin-scaffolder-backend |
| GHSA-mfvq-x7vr-rgqg Backstage: Secret-derived values may be exposed in scaffolder task logs | Medium | Also affects @backstage/plugin-scaffolder-backend |
| GHSA-29gx-h2m3-xw44 Backstage's scaffolder credential handling may allow unintended GitHub authentication fallback | Medium | Also affects @backstage/plugin-scaffolder-backend |
| GHSA-7hfw-grcm-cqm6 Backstage: Incorrect authorization in scaffolder task listing | Medium | Also affects @backstage/plugin-scaffolder-backend |
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