OpenStack Nova before 2012.1 allows someone with access to an EC2_ACCESS_KEY (equivalent to a username) to obtain the EC2_SECRET_KEY (equivalent to a password). Exposing the EC2_ACCESS_KEY via http or tools that allow man-in-the-middle over https could allow an attacker to easily obtain the EC2_SECRET_KEY. An attacker could also presumably brute force values for EC2_ACCESS_KEY.

Versions of nova before 2012.1 could expose hypervisor host files to a guest operating system when processing a maliciously constructed qcow filesystem.

Openstack Compute (Nova) Folsom, 2012.1, and 2011.3 does not limit the number of security group rules, which allows remote authenticated users with certain permissions to cause a denial of service (CPU and hard drive consumption) via a network request that triggers a large number of iptables rules.

Nova 2011.3 and Essex, when using the OpenStack API, allows remote authenticated users to bypass access restrictions for tenants of other users via an OSAPI request with a modified project_id URI parameter.

Multiple directory traversal vulnerabilities in OpenStack Nova before 2011.3.1, when the EC2 API and the S3/RegisterImage image-registration method are enabled, allow remote authenticated users to overwrite arbitrary files via a crafted (1) tarball or (2) manifest.