Every CVE Search/ Get API key

CVE-2021-32836

Pre-auth unsafe deserialization in ZStack

7.5 High

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.

Attack profile

How easy it is to exploit

Attack vector
Network
Complexity
High
Privileges needed
None
User interaction
None

What an attacker can affect

Confidentiality
None
Integrity
Low
Availability
High

Exploit likelihood

2.04%Up 0.3 points since Sep 9, 2021
90%50%10%1%

What each source reports

CVE List Score used 7.5

Pre-auth unsafe deserialization in ZStack

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.

Record
CVE-2021-32836
CVSS 3.1
7.5 HighCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:H
Weakness
CWE-94
Updated
2026-11-02
EUVDEUVD-2021-19574 7.5

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.

Record
EUVD-2021-19574
CVSS 3.1
7.5 HighCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:H
Updated
2026-11-03
GitHub AdvisoriesGHSA-gpj5-98pq-4552 8.1

ZStack is open source IaaS(infrastructure as a service) software. In ZStack before versions 3.10...

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.

Record
GHSA-gpj5-98pq-4552
CVSS 3.1
8.1 HighCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness
CWE-94, CWE-502
Updated
2026-11-02
NVD 7.5

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.

Record
CVE-2021-32836
CVSS 3.1
7.5 HighCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:H
CVSS 3.1
8.1 HighCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS 2.0
6.8 MediumAV:N/AC:M/Au:N/C:P/I:P/A:P
Weakness
CWE-94, CWE-502
Updated
2026-11-02

Affected products

History

History
RecordedChangedSources
aliasesEUVD
first indexedCVE List, GitHub Advisories, NVD

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2021-32836 is a high vulnerability (CVSS 7.5) in Zstack, published September 9, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 2.04%, the 81st percentile. No source names a fixed version.

References

MoveEnter Open