A heap-based buffer overflow flaw was found in socat with data that happens to be output on the READLINE address. The READLINE address is usually only used interactively, without the "prompt" and "noprompt" options. If an attacker were able to provide malicious data to the other (arbitrary) address that is then transferred to socat's READLINE address for output, they would be able to execute arbitrary code with the privileges of the socat process.
To work around this flaw, you can use the "prompt" or "noprompt" options with the READLINE address.
This has been corrected upstream  in versions 22.214.171.124 and 2.0.0-b5; patches are available.
Created socat tracking bugs for this issue
Affects: fedora-all [bug 821553]
Affects: epel-all [bug 821554]