Ciphers with 64-bit block sizes used in CBC mode were found to be vulnerable to birthday attack when key renegotiation doesn't happen frequently or at all in long running connections. Blowfish cipher as used in OpenVPN by default is vulnerable to this attack, that allows remote attacker to recover partial plaintext information (XOR of two plaintext blocks).
Upstream: Karthikeyan Bhargavan (Inria), Gaëtan Leurent (Inria)
Created openvpn tracking bugs for this issue:
Affects: fedora-all [bug 1369833]
Affects: epel-all [bug 1369834]
This CVE Bugzilla entry is for community support informational purposes only as it does not affect a package in a commercially supported Red Hat product. Refer to the dependent bugs for status of those individual community products.