CVE Vulnerabilities

CVE-2021-32827

Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')

Published: Aug 16, 2021 | Modified: Nov 21, 2024
CVSS 3.x
9.6
CRITICAL
Source:
NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
CVSS 2.x
6.8 MEDIUM
AV:N/AC:M/Au:N/C:P/I:P/A:P
RedHat/V2
RedHat/V3
Ubuntu

MockServer is open source software which enables easy mocking of any system you integrate with via HTTP or HTTPS. An attacker that can trick a victim into visiting a malicious site while running MockServer locally, will be able to run arbitrary code on the MockServer machine. With an overly broad default CORS configuration MockServer allows any site to send cross-site requests. Additionally, MockServer allows you to create dynamic expectations using Javascript or Velocity templates. Both engines may allow an attacker to execute arbitrary code on-behalf of MockServer. By combining these two issues (Overly broad CORS configuration + Script injection), an attacker could serve a malicious page so that if a developer running MockServer visits it, they will get compromised. For more details including a PoC see the referenced GHSL-2021-059.

Weakness

The product constructs all or part of a command, data structure, or record using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify how it is parsed or interpreted when it is sent to a downstream component.

Affected Software

Name Vendor Start Version End Version
Mockserver Mock-server * *

Potential Mitigations

References