How severe is CVE-2026-106501?

CVE-2026-106501 has a CVSS score of 9.6/10, rated CRITICAL. Immediate patching is strongly recommended.

Which packages are affected by CVE-2026-106501?

CVE-2026-106501 affects the following packages: @backstage/plugin-scaffolder-backend (npm), @backstage/plugin-scaffolder-backend (npm), @backstage/plugin-scaffolder-backend (npm), @backstage/plugin-scaffolder-backend (npm). Ecosystems affected: npm.

How do I fix CVE-2026-106501?

Update @backstage/plugin-scaffolder-backend to 3.3.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-106501 is resolved across your whole dependency graph.

How do I detect CVE-2026-106501 in my npm dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for @backstage/plugin-scaffolder-backend, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2026-106501 if there is no patch (or I can't update yet)?

Assume what was exposed is already known: rotate any credential, token or key that the affected component could return, restrict the endpoint to callers that genuinely need it, and strip sensitive fields from responses and error output at the boundary rather than relying on the client not to read them.

Is CVE-2026-106501 actively exploited in the wild?

No public exploit code has been indexed for CVE-2026-106501 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2026-106501?

CVE-2026-106501 has an EPSS (Exploit Prediction Scoring System) score of 0.5%, placing it in the 41th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2026-106501?

CVE-2026-106501 is classified as Information Exposure (CWE-200), CWE-201 (CWE-201). These weakness types describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2026-106501 published, and has it been updated?

CVE-2026-106501 was published on October 6, 2026 and was last updated on October 21, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

📦

📦 npm

Not in CISA KEV

CRITICAL severity

CVE-2026-106501 — @backstage/plugin-scaffol…

CRITICALFix: backstage/backstage@66d2219

CVE-2026-106501 is a critical-severity (CVSS 9.6) Information Exposure vulnerability in @backstage/plugin-scaffolder-backend. A fix is available for @backstage/plugin-scaffolder-backend — see the affected versions and patch details below.

Backstage: Sensitive information exposure in Scaffolder

Also known asGHSA-g2v8-7jhw-pp8p

Published

Oct 6, 2026

Updated

Oct 21, 2026

Affected

4 pkgs

Patched

4 / 4

Exploits

None indexed

Exploitation data as of Oct 22, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

A successful exploit gives an attacker total control of the affected component, not partial access.
CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for CVE-2026-106501.

EPSS Exploitation Probability

via FIRST.org ↗

0.5%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs41th percentile — riskier than 41% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

CVE-2026-106501 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.

Where this sits among everything scored

Of 394,415 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.

Real-World Exposure

4 pkgs affected

📦@backstage/plugin-scaffolder-backend📦@backstage/plugin-scaffolder-backend📦@backstage/plugin-scaffolder-backend📦@backstage/plugin-scaffolder-backend

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects npm packages — download data is not available via public APIs for these ecosystems.

Description

Impact

An authenticated Backstage user who can read another user's Scaffolder task may receive internal execution data. In deployments where that data contains credentials for an external service, this may permit disclosure and unauthorized changes in that external service.

Patches

Patched in @backstage/plugin-scaffolder-backend version 4.1.0

Workarounds

Configure scaffolder.task.read with the isTaskOwner condition so users can only read tasks they created.
Restrict affected integrations and workflows to trusted operators until an upgrade is available.

Affected Packages

4 total 4 fixed

Ecosystem	Package	Vulnerable range	Fix
📦npm	`@backstage/plugin-scaffolder-backend`	all versions	3.3.1`npm install @backstage/plugin-scaffolder-backend@3.3.1`
📦npm	`@backstage/plugin-scaffolder-backend`	≥ 3.4.0&&< 3.4.1	3.4.1`npm install @backstage/plugin-scaffolder-backend@3.4.1`
📦npm	`@backstage/plugin-scaffolder-backend`	≥ 4.0.0&&< 4.0.3	4.0.3`npm install @backstage/plugin-scaffolder-backend@4.0.3`
📦npm	`@backstage/plugin-scaffolder-backend`	≥ 4.0.4&&< 4.1.0	4.1.0`npm install @backstage/plugin-scaffolder-backend@4.1.0`

Affected Products

2 products · 7 configurations

Application

backstagelinuxfoundation

≥ 1.51.0 && < 1.54.6

range

Application

backstage\/plugin-scaffolder-backendlinuxfoundation

≥ 4.0.4 && < 4.1.0

range

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for @backstage/plugin-scaffolder-backend, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update @backstage/plugin-scaffolder-backend to 3.3.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-106501 is resolved across your whole dependency graph.
Workarounds
Assume what was exposed is already known: rotate any credential, token or key that the affected component could return, restrict the endpoint to callers that genuinely need it, and strip sensitive fields from responses and error output at the boundary rather than relying on the client not to read them.

Fixing This On Your OS

If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.

Red HatImportant

This vulnerability is rated as an Important impact because authenticated users with read permissions to Scaffolder tasks can inspect internal run data, which may contain sensitive secrets or tokens for integrated downstream services. In environments running Red Hat Developer Hub and Ansible Automation Platform Portal…

Workaround published by Red Hat

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.

Source: Red Hat security advisory for CVE-2026-106501 (CC BY 4.0)

Product	Fixed in	Advisory
Red Hat Ansible Automation Platform 2.2	`ansible-automation-platform/automation-portal:1792523640`	RHSA-2026:86675

Frequently Asked Questions

### Impact An authenticated Backstage user who can read another user's Scaffolder task may receive internal execution data. In deployments where that data contains credentials for an external service, this may permit disclosure and unauthorized changes in that external service. ### Patches Patched in `@backstage/plugin-scaffolder-backend` version `4.1.0` ### Workarounds - Configure `scaffolder.task.read` with the `isTaskOwner` condition so users can only read tasks they created. - Restrict affected integrations and workflows to trusted operators until an upgrade is available.