RCE in Zstack

CVE-2021-32836

ZStack is open source IaaS(infrastructure as a service) software. In ZStack before versions 3.10.12 and 4.1.6 there is a pre-auth unsafe deserialization vulnerability in the REST API. An attacker in control of the request body will be able to provide both the class name and the data to be deserialized and therefore will be able to instantiate an arbitrary type and assign arbitrary values to its fields. This issue may lead to a Denial Of Service. If a suitable gadget is available, then an attacker may also be able to exploit this vulnerability to gain pre-auth remote code execution. For additional details see the referenced GHSL-2021-087.

Vulnerability class: RCE (Remote Code Execution)

EPSS: 0.020 (79.1th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2021-32836?
CVE-2021-32836 is a high-severity vulnerability in Zstack, classified under Code Injection. CVSS score: 7.5/10. Published 2021-09-09.
How severe is CVE-2021-32836?
High severity. CVSS v3 base score is 7.5 out of 10.