Hi, relay operators!
There have been a series of new openssl releases today: 0.9.8zg, 1.0.0s, 1.0.1n, and 1.0.2b.
They fix a set of security issues described in this announcement: https://www.openssl.org/news/secadv_20150611.txt
Since some of these issues could allow a remote denial-of-service attack, I would suggest that everybody should upgrade as OpenSSL packages become available for your operating systems. If you build OpenSSL from source, now's a good time to rebuild. You probably don't need to run in circles freaking out, or anything -- just upgrade when you can.
Also, if you can possibly avoid it, it would be a good idea to stop using the OpenSSL 0.9.8 series entirely. It's old and crufty and is missing many security improvements in later versions. OpenSSL 0.9.8 will not be supported in Tor 0.2.7.2-alpha or later.
best wishes, and many thanks! -- Nick Mathewson