CVE-2014-1420

On desktop, Ubuntu UI Toolkits StateSaver would serialise data on tmp/ files which an attacker could use to expose potentially sensitive data. StateSaver would also open files without the O_EXCL flag. An attacker could exploit this to launch a symlink attack, though this is partially mitigated by symlink and hardlink restrictions in Ubuntu. Fixed in 1.1.1188+14.10.20140813.4-0ubuntu1.

Weakness

The product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource.

Affected Software

Potential Mitigations

• Follow the principle of least privilege when assigning access rights to entities in a software system.
• Denying access to a file can prevent an attacker from replacing that file with a link to a sensitive file. Ensure good compartmentalization in the system to provide protected areas that can be trusted.

Related Attack Patterns

• https://cwe.mitre.org/data/definitions/132.html
• https://cwe.mitre.org/data/definitions/17.html
• https://cwe.mitre.org/data/definitions/35.html
• https://cwe.mitre.org/data/definitions/76.html

References

• http://bazaar.launchpad.net/~ubuntu-sdk-team/ubuntu-ui-toolkit/staging/revision/1182
• https://launchpad.net/bugs/1348241
• http://bazaar.launchpad.net/~ubuntu-sdk-team/ubuntu-ui-toolkit/staging/revision/1182
• https://launchpad.net/bugs/1348241