adding security release

Author: vsoch

_posts/2017-02-14-release-2-2-1.md

@@ -0,0 +1,25 @@
+---
+title:  "Singularity 2.2.1 Security Release"
+category: releases
+permalink: "release-2-2-1"
+version: "2.2.1"
+---
+
+For the full release announcement and downloads, please see <a target="_blank" href="https://github.com/singularityware/singularity/releases/tag/2.2.1">the release on Github</a>.
+
+This release includes a fix for a Moderate Severity security issue, and other improvements to version 2.2.
+
+## Security information:
+
+In versions of Singularity previous to 2.2.1, it was possible for a malicious user to create and manipulate specifically crafted raw devices within containers they own. Utilizing `MS_NODEV` as a container image mount option mitigates this potential vector of attack. As a result, this update should be implemented with high urgency. A big thanks to Mattias Wadenstein (@UMU in Sweden) for identifying and reporting this issue!
+
+
+### Other improvements:
+
+* Fixed some leaky file descriptors
+* Cleaned up `*printf()` usage
+* Catch if user's group is not properly defined
+
+Please report any additional bugs <a href="https://github.com/singularityware/singularity/issues/new" target="_blank">as issues</a>.
+
+Thank you!