CVE-2024-50386 Apache CloudStack: Directly downloaded templates can be used to abuse KVM-based infrastructure

High 8.5 Published 12 Nov 2024 Updated 12 Nov 2024

Attackers can register malicious KVM templates to compromise host filesystems and infrastructure integrity in Apache CloudStack.

Exploited in the wild: Not known
Login needed: Any signed-in user
Attackable: Over the internet
Victim action needed: Not needed
Fix: None listed

What is CVE-2024-50386?

CVE-2024-50386 is a high-severity missing authorization vulnerability in Apache Cloudstack, published on 12 Nov 2024. Any signed-in user can exploit it over the network, with no action from the victim.

Official description

Account users in Apache CloudStack by default are allowed to register templates to be downloaded directly to the primary storage for deploying instances. Due to missing validation checks for KVM-compatible templates in CloudStack 4.0.0 through 4.18.2.4 and 4.19.0.0 through 4.19.1.2, an attacker that can register templates, can use them to deploy malicious instances on KVM-based environments and exploit this to gain access to the host filesystems that could result in the compromise of resource integrity and confidentiality, data loss, denial of service, and availability of KVM-based infrastructure managed by CloudStack.

Users are recommended to upgrade to Apache CloudStack 4.18.2.5 or 4.19.1.3, or later, which addresses this issue.

Additionally, all user-registered KVM-compatible templates can be scanned and checked that they are flat files that should not be using any additional or unnecessary features. For example, operators can run the following command on their file-based primary storage(s) and inspect the output. An empty output for the disk being validated means it has no references to the host filesystems; on the other hand, if the output for the disk being validated is not empty, it might indicate a compromised disk. However, bear in mind that (i) volumes created from templates will have references for the templates at first and (ii) volumes can be consolidated while migrating, losing their references to the templates. Therefore, the command execution for the primary storages can show both false positives and false negatives.

for file in $(find /path/to/storage/ -type f -regex [a-f0-9\-]*.*); do echo "Retrieving file [$file] info. If the output is not empty, that might indicate a compromised disk; check it carefully."; qemu-img info -U $file | grep file: ; printf "\n\n"; done For checking the whole template/volume features of each disk, operators can run the following command:

for file in $(find /path/to/storage/ -type f -regex [a-f0-9\-]*.*); do echo "Retrieving file [$file] info."; qemu-img info -U $file; printf "\n\n"; done

Weakness: CWE-20

Which versions are affected by CVE-2024-50386?

It affects 1 product.

Products include Apache Cloudstack.

How do I fix CVE-2024-50386?

No fix has been published for CVE-2024-50386 yet. Limit exposure of the affected software until one is available.

Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.

Is CVE-2024-50386 being exploited?

There is no known exploitation of CVE-2024-50386 in the wild and no public exploit code.

All Apache Cloudstack vulnerabilities

Sources

Also known as GHSA-5pg9-rxpc-jxgf.