Code Execution Flaws Patched in Apache OpenOffice

Researchers at Cisco Talos have discovered three vulnerabilities in Apache OpenOffice that can be exploited by malicious actors for remote code execution using specially crafted document files.

Talos has classified the flaws as “high severity” with a CVSS score of 8.3, but the open source software’s developers have assigned them a severity rating of only “medium.”

The security holes, tracked as CVE-2017-9806, CVE-2017-12607 and CVE-2017-12608, affect the WW8Fonts and ImportOldFormatStyles components of the Writer application, and the PPTStyleSheet functionality in the Draw application.

An attacker can create special documents that trigger an out-of-bounds write, which can be leveraged to cause the application to enter a denial-of-service (DoS) condition and crash, or execute arbitrary code.

The vulnerabilities affect Apache OpenOffice versions 4.1.3 and prior, along with OpenOffice.org. Patches are included in version 4.1.4, which the Apache Software Foundation announced earlier this month.

While there is no evidence of exploitation in the wild, Cisco Talos has published detailed technical information that can be used to launch attacks.

“Vulnerabilities in office suite software such as word processors are very useful to attackers for client side attacks. Attackers often send malicious documents attached to emails exploiting such vulnerabilities to execute malicious commands when the victim is tricked into opening the file through some form of social engineering,” Talos researchers said in a blog post.

Last year, Cisco Talos researchers reported finding similar vulnerabilities in the open source office suite LibreOffice.

“We have monitored many campaigns using this attack vector for targeted attacks. The recently analysed attack against South Korean users is a good example. The adversaries used a vulnerability in the Hangul Word Processor(HWP) to infect their victims,” they added. “This shows how important it is to keep all applications up to date and not only the operating system.”