NVD / CVE Program· CNA GitHub_M

CVE-2025-55285: @backstage/plugin-scaffolder-backend Template Secret Leakage in Logs in Scaffolder When Using `fetch:template`

Noroxi assessment

Priority: Monitor (action score 10/100)

The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
Probability of exploitation in the next 30 days: 0.24% (FIRST EPSS).
Anyone who can reach it over the internet can trigger it. Administrator privileges are required. A user must open a link or visit a page. Special conditions such as timing or configuration are required.
Fixed version: @backstage/plugin-scaffolder-backend (npm) 2.1.1.

Low priority for now. Upgrade to @backstage/plugin-scaffolder-backend (npm) 2.1.1 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

@backstage/plugin-scaffolder-backend is the backend for the default Backstage software templates. Prior to version 2.1.1, duplicate logging of the input values in the fetch:template action in the Scaffolder meant that some of the secrets were not properly redacted. If ${{ secrets.x }} is not passed through to fetch:template there is no impact. This issue has been resolved in 2.1.1 of the scaffolder-backend plugin. A workaround for this issue involves Template Authors removing the use of ${{ secrets }} being used as an argument to fetch:template.

LowCVSS 2.6 · v3.1—No exploit Fix available

Info leak

GHSA-3x3q-ghcp-whf7

Published: Aug 15, 2025
Updated: Jun 17, 2026
EPSS: 0.2% · 15th percentile
CWE: CWE-532

Report tools

JSON

Action score

Monitor

Low priority for now.

CVSS: 10 / 40 · 2.6 / 10
CISA KEV: 0 / 30 · Not listed
EPSS: 0 / 30 · 0.2%

CISA SSVC decision

Exploitation: none
Automatable: no
Technical impact: partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD: —
CNA · GitHub_M: 2.6; NVD has not scored this yet; the score shown is the CNA’s.

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

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Not in KEV: no record of exploitation in the wild
No public exploit code on record
A fix has been released

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

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Versions reported by the vendor

Affected version ranges reported by the assigning authority (GitHub_M). Independent of NVD's CPE analysis and usually ahead of it.

backstage backstage
- < 2.1.1affected

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

Ecosystem	Package	Affected range	Fix
npm	@backstage/plugin-scaffolder-backend	before 2.1.1	2.1.1

Same product

backstage: all records

Other highest-scoring records for the same primary product.

CVE-2026-106557Backstage: Improper input validation in TechDocs Markdown extension configuration
30Monitor
CVE-2026-24046Backstage has a Possible Symlink Path Traversal in Scaffolder Actions
28Monitor
CVE-2026-115923Backstage catalog rules can be bypassed for URL locations using encoded path segments
26Monitor

Published before and after this one in the same product

← EarlierCVE-2024-53983Nov 29, 2024 · Server-side request forgery in Backstage Scaffolder plugin
21Monitor
← EarlierCVE-2025-32791Apr 16, 2025 · Permission policy information leakage in Backstage permission system
17Monitor
Later →CVE-2026-24047Jan 21, 2026 · @backstage/cli-common has a possible `resolveSafeChildPath` Symlink Chain Bypass
25Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / package	Fixed version	Source
npm:@backstage/plugin-scaffolder-backend	2.1.1	Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

backstage/backstagecommit c371f6f

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

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Bug bounty scope