CVE-2021-43776 XSS vulnerability in @backstage/plugin-auth-backend

2021-11-2618:15:10

CWE-79

GitHub_M

www.cve.org

cve-2021-43776

xss vulnerability

@backstage/plugin-auth-backend

malicious actor

access tokens

secrets

default csp

patch

CVSS3

7.4

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

NONE

User Interaction

REQUIRED

Scope

CHANGED

Confidentiality Impact

HIGH

Integrity Impact

NONE

Availability Impact

NONE

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

EPSS

0.001

Percentile

29.9%

JSON

Backstage is an open platform for building developer portals. In affected versions the auth-backend plugin allows a malicious actor to trick another user into visiting a vulnerable URL that executes an XSS attack. This attack can potentially allow the attacker to exfiltrate access tokens or other secrets from the user’s browser. The default CSP does prevent this attack, but it is expected that some deployments have these policies disabled due to incompatibilities. This is vulnerability is patched in version 0.4.9 of @backstage/plugin-auth-backend.

CNA Affected

[
  {
    "product": "backstage",
    "vendor": "backstage",
    "versions": [
      {
        "status": "affected",
        "version": "< 0.4.9"
      }
    ]
  }
]