An unofficial patch has been made available for a recently disclosed remote code execution vulnerability affecting the Apache OpenOffice open source productivity suite.
The flaw, described as a path traversal issue and tracked as CVE-2018-16858, was disclosed in early February by researcher Alex Inführ. The expert found that a hacker could execute code on a system by getting the targeted user to open a specially crafted document that loaded a Python file placed by the attacker anywhere on the device.
The attack involves a document containing a specially crafted link pointing to a Python script. When the victim opens the document and hovers over the link, the malicious code gets executed without any warning message being displayed. In order to avoid raising suspicion and make the attack more likely to succeed, a hacker can create a document where the entire page is filled with links whose color has been set to white – this way the victim only sees a blank page before the exploit is executed.
Inführ says the vulnerability impacts both LibreOffice and OpenOffice. However, LibreOffice developers released a patch less than two weeks after being notified.
OpenOffice developers, however, do not appear to have issued any fixes and have not made any comments on the vulnerability. SecurityWeek has reached out to them more than one week ago, but received no response.
ACROS Security’s 0patch service has released an unofficial patch for OpenOffice to address this vulnerability. The micropatch can be applied to the latest version of OpenOffice for Windows. Micropatches have been released for LibreOffice as well.
0patch has published a video showing an exploit attempt without and with the patch applied: