CVE-2021-32827

Public Exploit
Arbitrary code execution in MockServer

Description

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.

Categories

6.1
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.25%
Third-Party Advisory github.com Third-Party Advisory oracle.com
Affected: mock-server mockserver
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2021-32827?
CVE-2021-32827 has been scored as a medium severity vulnerability.
How to fix CVE-2021-32827?
To fix CVE-2021-32827, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-32827 being actively exploited in the wild?
It is possible that CVE-2021-32827 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-32827?
CVE-2021-32827 affects mock-server mockserver.
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