CVE-2021-43783 Path Traversal in @backstage/plugin-scaffolder-backend

2021-11-2919:20:09

CWE-22

GitHub_M

www.cve.org

cve-2021-43783

path traversal

@backstage/plugin-scaffolder-backend

vulnerability

version 0.15.14

scaffolder templates

access restriction

mitigation

CVSS3

8.5

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

LOW

User Interaction

NONE

Scope

CHANGED

Confidentiality Impact

NONE

Integrity Impact

HIGH

Availability Impact

LOW

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:L

AI Score

8.5

Confidence

High

EPSS

0.001

Percentile

32.5%

JSON

@backstage/plugin-scaffolder-backend is the backend for the default Backstage software templates. In affected versions a malicious actor with write access to a registered scaffolder template is able to manipulate the template in a way that writes files to arbitrary paths on the scaffolder-backend host instance. This vulnerability can in some situation also be exploited through user input when executing a template, meaning you do not need write access to the templates. This method will not allow the attacker to control the contents of the injected file however, unless the template is also crafted in a specific way that gives control of the file contents. This vulnerability is fixed in version 0.15.14 of the @backstage/plugin-scaffolder-backend. This attack is mitigated by restricting access and requiring reviews when registering or modifying scaffolder templates.

CNA Affected

[
  {
    "product": "backstage",
    "vendor": "backstage",
    "versions": [
      {
        "status": "affected",
        "version": "< 0.15.14"
      }
    ]
  }
]