Instances deployed via the Proxmox extension allow unauthorized access to instances belonging to other tenants.

This issue affects Apache CloudStack: from 4.21.0.0 through 4.22.0.0.

The Proxmox extension for CloudStack improperly uses a user-editable instance setting, proxmoxvmid, to associate CloudStack instances with Proxmox virtual machines. Because this value is not restricted or validated against tenant ownership and Proxmox VM IDs are predictable, a non-privileged attacker can modify the setting to reference a VM belonging to another account. This allows unauthorized cross-tenant access and enables full control over the targeted VM, including starting, stopping, and destroying the virtual machine.

Users are recommended to upgrade to version 4.22.0.1, which fixes this issue.

As a workaround for the existing installations, editing of the proxmoxvmid instance detail by users can be prevented by adding this detail name to the global configuration parameter - user.vm.denied.details.

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

The CloudStack cluster service runs on unauthenticated port (default 9090) that can be misused to run arbitrary commands on targeted hypervisors and CloudStack management server hosts. Some of these commands were found to have command injection vulnerabilities that can result in arbitrary code execution via agents on the hosts that may run as a privileged user. An attacker that can reach the cluster service on the unauthenticated port (default 9090), can exploit this to perform remote code execution on CloudStack managed hosts and result in complete compromise of the confidentiality, integrity, and availability of CloudStack managed infrastructure.

Users are recommended to restrict the network access to the cluster service port (default 9090) on a CloudStack management server host to only its peer CloudStack management server hosts. Users are recommended to upgrade to version 4.18.2.1, 4.19.0.2 or later, which addresses this issue.

The CloudStack integration API service allows running its unauthenticated API server (usually on port 8096 when configured and enabled via integration.api.port global setting) for internal portal integrations and for testing purposes. By default, the integration API service port is disabled and is considered disabled when integration.api.port is set to 0 or negative. Due to an improper initialisation logic, the integration API service would listen on a random port when its port value is set to 0 (default value). An attacker that can access the CloudStack management network could scan and find the randomised integration API service port and exploit it to perform unauthorised administrative actions and perform remote code execution on CloudStack managed hosts and result in complete compromise of the confidentiality, integrity, and availability of CloudStack managed infrastructure.

Users are recommended to restrict the network access on the CloudStack management server hosts to only essential ports. Users are recommended to upgrade to version 4.18.2.1, 4.19.0.2 or later, which addresses this issue.

By default the CloudStack management server honours the x-forwarded-for HTTP header and logs it as the source IP of an API request. This could lead to authentication bypass and other operational problems should an attacker decide to spoof their IP address this way. Users are recommended to upgrade to CloudStack version 4.18.1.1 or 4.19.0.1, which fixes this issue.

Apache CloudStack version 4.5.0 and later has a SAML 2.0 authentication Service Provider plugin which is found to be vulnerable to XML external entity (XXE) injection. This plugin is not enabled by default and the attacker would require that this plugin be enabled to exploit the vulnerability. When the SAML 2.0 plugin is enabled in affected versions of Apache CloudStack could potentially allow the exploitation of XXE vulnerabilities. The SAML 2.0 messages constructed during the authentication flow in Apache CloudStack are XML-based and the XML data is parsed by various standard libraries that are now understood to be vulnerable to XXE injection attacks such as arbitrary file reading, possible denial of service, server-side request forgery (SSRF) on the CloudStack management server.

A buffer overflow vulnerability has been found in the baremetal component of Apache CloudStack. This applies to all versions prior to 4.13.1. The vulnerability is due to the lack of validation of the mac parameter in baremetal virtual router. If you insert an arbitrary shell command into the mac parameter, v-router will process the command. For example: Normal: http://{GW}:10086/baremetal/provisiondone/{mac}, Abnormal: http://{GW}:10086/baremetal/provisiondone/#';whoami;#. Mitigation of this issue is an upgrade to Apache CloudStack 4.13.1.0 or beyond.

Apache CloudStack 4.1 to 4.8.1.0 and 4.9.0.0 contain an API call designed to allow a user to register for the developer API. If a malicious user is able to determine the ID of another (non-"root") CloudStack user, the malicious user may be able to reset the API keys for the other user, in turn accessing their account and resources.

Apache CloudStack before 4.5.2 does not properly preserve VNC passwords when migrating KVM virtual machines, which allows remote attackers to gain access by connecting to the VNC server.

Citrix Cloud.com CloudStack, and Apache CloudStack pre-release, allows remote attackers to make arbitrary API calls by leveraging the system user account, as demonstrated by API calls to delete VMs.