Can't install any plugin in ElasticSearch 2.1

I have a server (running Suse Linux Enterprise Server) and I have ElasticSearch 2.1 installed and seemingly working.

Now, I'm trying to install the head plugin but it does not work. I've tried:

# /usr/share/elasticsearch/bin/plugin install head --verbose
-> Installing head...
Trying https://download.elastic.co/elasticsearch/release/org/elasticsearch/plugin/head/2.1.0/head-2.1.0.zip ...
Failed: SocketException[java.security.NoSuchAlgorithmException: Error constructing implementation (algorithm: Default, provider: SunJSSE, class: sun.security.ssl.SSLContextImpl$DefaultSSLContext)]; nested: NoSuchAlgorithmException[Error constructing implementation (algorithm: Default, provider: SunJSSE, class: sun.security.ssl.SSLContextImpl$DefaultSSLContext)]; nested: ProviderException[nextBytes() failed]; nested: IOException[Bad file descriptor]; 
ERROR: failed to download out of all possible locations..., use --verbose to get detailed information

I've also tried using the full path from Github:

# /usr/share/elasticsearch/bin/plugin install mobz/elasticsearch-head --verbose
-> Installing mobz/elasticsearch-head...
Trying https://github.com/mobz/elasticsearch-head/archive/master.zip ...
Failed: SocketException[java.security.NoSuchAlgorithmException: Error constructing implementation (algorithm: Default, provider: SunJSSE, class: sun.security.ssl.SSLContextImpl$DefaultSSLContext)]; nested: NoSuchAlgorithmException[Error constructing implementation (algorithm: Default, provider: SunJSSE, class: sun.security.ssl.SSLContextImpl$DefaultSSLContext)]; nested: ProviderException[nextBytes() failed]; nested: IOException[Bad file descriptor]; 
ERROR: failed to download out of all possible locations..., use --verbose to get detailed information

How can I fix that? Looks like a Java-related error. I'm running OpenJDK:

# java -version
java version "1.7.0_95"
OpenJDK Runtime Environment (IcedTea 2.6.4) (suse-24.2-x86_64)
OpenJDK 64-Bit Server VM (build 24.95-b01, mixed mode)

Thanks.

Your Java is broken.

Install Java security certificates.