@backstage/backend-app-api leaks GitLab access tokens

Description

A flaw was found in the Red Hat Developer Hub (RHDH). The catalog-import function leaks GitLab access tokens on the frontend when the base64 encoded GitLab token includes a newline at the end of the string. The sanitized error can display on the frontend, including the raw access token. Upon gaining access to this token and depending on permissions, an attacker could push malicious code to repositories, delete resources in Git, revoke or generate new keys, and sign code illegitimately.

Basic information

Type
reviewed
Severity
high
Advisory on GitHub
Open advisory ↗
Repository advisory
Source code
Browse source ↗
Published (advisory)
2024-01-04 12:30:20 UTC
Updated
2025-10-01 20:11:28 UTC
GitHub reviewed
2024-02-05 17:59:41 UTC
NVD published
2024-01-04

EPSS Score

Score Percentile
0.22% 44.13%

CVSS Scores

Base score Version Severity Vector
7.3 3.1
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/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:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.

Identifiers

CWEs

CWE id Name
CWE-200 Exposure of Sensitive Information to an Unauthorized Actor
CWE-209 Generation of Error Message Containing Sensitive Information

Credits

  • pfeifferj (analyst)

Affected packages (1)

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

Ecosystem Package Vulnerable range First patched Vulnerable functions
npm @backstage/backend-app-api < 0.5.9-next.1 0.5.9-next.1

References

cvelogic Threat Intelligence