Users of OpenOffice for Windows, Mac and Linux can all be affected. Below is the text of an alert that I received from Apache:
[i]CVE-2015-1774
OpenOffice HWP Filter Remote Code Execution and Denial of Service
Vulnerability
A vulnerability in OpenOffice's HWP filter allows attackers to cause a
denial of service (memory corruption and application crash) or possibly
execution of arbitrary code by preparing specially crafted documents in
the HWP document format.
Severity: Important
Vendor: The Apache Software Foundation
Versions Affected:
All Apache OpenOffice versions 4.1.1 and older are affected.
Mitigation:
Apache OpenOffice users are advised to remove the problematic library in
the "program" folder of their OpenOffice installation. On Windows it is
named "hwp.dll", on Mac it is named "libhwp.dylib" and on Linux it is
named "libhwp.so". Alternatively the library can be renamed to anything
else e.g. "hwp_renamed.dll".
This mitigation will drop AOO's support for documents created in "Hangul
Word Processor" versions from 1997 or older. Users of such documents are
advised to convert their documents to other document formats such as
OpenDocument before doing so.
Apache OpenOffice aims to fix the vulnerability in version 4.1.2.
Credits:
Thanks to an anonymous contributor working with VeriSign iDefense Labs.[/i]