It was reported , that an error when processing DHCP requests with the 'Relay Agent Information' option (82) in src/lib/dhcp.c could be exploited to cause an infinite loop, in the process denying further requests via a packet with multiple sub-options.
According to the upstream report, this flaw seems to only affect 2.1.9 and was fixed  in 2.1.10.
The offending file (dhcp.c) is not present in the version of freeradius as provided with Red Hat Enterprise Linux 5 (1.1.3).
This issue has been assigned the name CVE-2010-3696.
Created freeradius tracking bugs for this issue
Affects: fedora-all [bug 639490]
It would help to talk to the vendor before requesting a CVE, and filing a
1) the code is *not* built as part of the default installation
You have to go out of your way to enable it
2) the functionality is marked as "not for production use".
i.e. if it affects your production network, it's not our fault
i.e. this is NOT a security issue in any binary shipped by any OS vendor. It is not a security issue in the default installation of FreeRADIUS.
As Alan commented above, DHCP support is not enabled upstream by default, and is not enabled in Fedora and Red Hat Enterprise Linux FreeRADIUS packages.
Alan, thank you for your comments!
Not vulnerable. This issue did not affect the versions of freeradius as shipped with Red Hat Enterprise Linux 4, 5, or 6.
Upstream has made the following public dispute to this flaw (http://freeradius.org/security.html):
2010.10.01 CVE-2010-3696 - This issue was filed without consulting with us, and we do not agree with the assessment.
The correct summary is that modifying the source code to the server can cause it to crash. The DHCP code is clearly marked "experimental", and is not normally included in the server binaries. It should be no surprise, therefore, that experimental and untested features do not work properly.
We recommend that people run experimental code in a closed environment. People who want a fix to this issue can upgrade to the latest version of the server.