CVE-2011-4596 - Path Traversal vulnerability in Openstack Nova

Attack vector
Attack complexity
Privileges required
Confidentiality impact
Integrity impact
Availability impact


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.

Vulnerable Configurations

Common Weakness Enumeration (CWE)

CWE-22 - Path Traversal

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Relative Path Traversal
    An attacker exploits a weakness in input validation on the target by supplying a specially constructed path utilizing dot and slash characters for the purpose of obtaining access to arbitrary files or resources. An attacker modifies a known path on the target in order to reach material that is not available through intended channels. These attacks normally involve adding additional path separators (/ or \) and/or dots (.), or encodings thereof, in various combinations in order to reach parent directories or entirely separate trees of the target's directory structure.
  • Directory Traversal
    An attacker with access to file system resources, either directly or via application logic, will use various file path specification or navigation mechanisms such as ".." in path strings and absolute paths to extend their range of access to inappropriate areas of the file system. The attacker attempts to either explore the file system for recon purposes or access directories and files that are intended to be restricted from their access. Exploring the file system can be achieved through constructing paths presented to directory listing programs, such as "ls" and 'dir', or through specially crafted programs that attempt to explore the file system. The attacker engaging in this type of activity is searching for information that can be used later in a more exploitive attack. Access to restricted directories or files can be achieved through modification of path references utilized by system applications.
  • File System Function Injection, Content Based
    An attack of this type exploits the host's trust in executing remote content including binary files. The files are poisoned with a malicious payload (targeting the file systems accessible by the target software) by the attacker and may be passed through standard channels such as via email, and standard web content like PDF and multimedia files. The attacker exploits known vulnerabilities or handling routines in the target processes. Vulnerabilities of this type have been found in a wide variety of commercial applications from Microsoft Office to Adobe Acrobat and Apple Safari web browser. When the attacker knows the standard handling routines and can identify vulnerabilities and entry points they can be exploited by otherwise seemingly normal content. Once the attack is executed, the attackers' program can access relative directories such as C:\Program Files or other standard system directories to launch further attacks. In a worst case scenario, these programs are combined with other propagation logic and work as a virus.
  • Using Slashes and URL Encoding Combined to Bypass Validation Logic
    This attack targets the encoding of the URL combined with the encoding of the slash characters. An attacker can take advantage of the multiple way of encoding an URL and abuse the interpretation of the URL. An URL may contain special character that need special syntax handling in order to be interpreted. Special characters are represented using a percentage character followed by two digits representing the octet code of the original character (%HEX-CODE). For instance US-ASCII space character would be represented with %20. This is often referred as escaped ending or percent-encoding. Since the server decodes the URL from the requests, it may restrict the access to some URL paths by validating and filtering out the URL requests it received. An attacker will try to craft an URL with a sequence of special characters which once interpreted by the server will be equivalent to a forbidden URL. It can be difficult to protect against this attack since the URL can contain other format of encoding such as UTF-8 encoding, Unicode-encoding, etc.
  • Manipulating Input to File System Calls
    An attacker manipulates inputs to the target software which the target software passes to file system calls in the OS. The goal is to gain access to, and perhaps modify, areas of the file system that the target software did not intend to be accessible.


  • NASL familyFedora Local Security Checks
    NASL idFEDORA_2011-17111.NASL
    descriptionAlso updates the libguestfs suppose Add --yes, --rootpw, and --novapw options to openstack-db-setup. Change the default database from sqlite to mysql. Note that Tenable Network Security has extracted the preceding description block directly from the Fedora security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.
    last seen2020-06-01
    plugin id57387
    reporterThis script is Copyright (C) 2011-2019 Tenable Network Security, Inc.
    titleFedora 16 : openstack-nova-2011.3-13.fc16 (2011-17111)
  • NASL familyFedora Local Security Checks
    NASL idFEDORA_2012-0682.NASL
    descriptionUpdate to 2011.3.1 release candidate. See This also includes a minor bug fix for libguestfs file injection This update includes ~50 patches from the upstream stable branch and a fix for an issue with attaching volumes. Sync up with Fedora spec, to only add fuse group if present. Explicitly depend on the fuse package to avoid #767852. Requires manually installing
    last seen2020-03-17
    plugin id57610
    reporterThis script is Copyright (C) 2012-2020 Tenable Network Security, Inc.
    titleFedora 16 : openstack-nova-2011.3.1-0.4.10818.fc16 (2012-0682)
  • NASL familyUbuntu Local Security Checks
    descriptionDavid Black discovered that Nova did not properly perform input validation during image registration. An attacker could exploit this by registering a crafted image using the EC2 API or S3/RegisterImage method and overwrite files as the nova user. Note that Tenable Network Security has extracted the preceding description block directly from the Ubuntu security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.
    last seen2020-06-01
    plugin id57306
    reporterUbuntu Security Notice (C) 2011-2019 Canonical, Inc. / NASL script (C) 2011-2019 and is owned by Tenable, Inc. or an Affiliate thereof.
    titleUbuntu 11.10 : nova vulnerability (USN-1305-1)