Apple · Ios · CVE-2016-1840
**Name of the Vulnerable Software and Affected Versions**
libxml2 versions prior to 2.9.4
Apple iOS versions prior to 9.3.2
OS X versions prior to 10.11.5
tvOS versions prior to 9.2.1
watchOS versions prior to 2.2.1
**Description**
The issue is caused by a heap-based buffer overflow in the `xmlFAParsePosCharGroup` function. This can be exploited by a remote attacker using a specially crafted XML document, potentially allowing them to execute arbitrary code or cause a denial of service due to memory corruption.
**Recommendations**
For libxml2 versions prior to 2.9.4, update to version 2.9.4 or later.
For Apple iOS versions prior to 9.3.2, update to version 9.3.2 or later.
For OS X versions prior to 10.11.5, update to version 10.11.5 or later.
For tvOS versions prior to 9.2.1, update to version 9.2.1 or later.
For watchOS versions prior to 2.2.1, update to version 2.2.1 or later.
As a temporary workaround, consider restricting the use of the `xmlFAParsePosCharGroup` function until a patch is available. Avoid using specially crafted XML documents that could exploit the buffer overflow vulnerability.