2016-01-15 - OpenSSL Vulnerabilities (SLOTH)

A detailed description of this issue can be seen in the following blog posting: http://www.mitls.org/pages/attacks/SLOTH

Advisory CVEs

CVE-2015-7575 - TLS 1.2 Transcript Collision attacks against MD5 in key exchange protocol (SLOTH)


xCAT uses OpenSSL for client-server communication but does not ship it.

It is highly recommended to keep your OpenSSL levels up-to-date with the indicated versions in the security bulletins to prevent any potential security threats. Obtain the updated software packages from your Operating system distribution channels.

Disable MD5 authentication in the cipher list using the site table keyword xcatsslciphers.

  1. Check if MD5 is already disabled: tabdump site | grep xcatssl
  2. If nothing is set, add ALL:!MD5 to the cipher list: chtab key=xcatsslciphers site.value='ALL:!MD5'
  3. Restart xcat: service xcatd restart