Backstage vulnerable to potential reading of SCM URLs using built in token

Description

Impact

A vulnerability in the SCM URL parsing used by Backstage integrations allowed path traversal sequences in encoded form to be included in file paths. When these URLs were processed by integration functions that construct API URLs, the traversal segments could redirect requests to unintended SCM provider API endpoints using the configured server-side integration credentials.

This affects instances that use any of the SCM integrations (GitHub, Bitbucket Server, Bitbucket Cloud) with the scaffolder or other features that accept user-provided SCM URLs.

Patches

This is patched in @backstage/integration version 1.20.1.

Workarounds

There is no workaround for this vulnerability. Users should upgrade to the patched version.

References

  • Backstage SCM integration documentation: https://backstage.io/docs/integrations/

Basic information

Type
reviewed
Severity
low
Advisory on GitHub
Open advisory ↗
Repository advisory
Open repository advisory ↗
Source code
Browse source ↗
Published (advisory)
2026-03-05 00:20:45 UTC
Updated
2026-03-09 15:46:53 UTC
GitHub reviewed
2026-03-05 00:20:45 UTC
NVD published
2026-03-07

EPSS Score

Score Percentile
0.02% 3.46%

CVSS Scores

Base score Version Severity Vector
2.7 3.1
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:N/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:H)
They need powerful rights—admin, root, or similar—before this pays off.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.

Identifiers

CWEs

CWE id Name
CWE-22 Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

Affected packages (1)

Vulnerable version ranges and first patched releases as published by GitHub.

Ecosystem Package Vulnerable range First patched Vulnerable functions
npm @backstage/integration <= 1.20.0 1.20.1

References

cvelogic Threat Intelligence