Simon L. Nielsen alerted vendor-sec to this issue:
While working on the FreeBSD Security Advisory for the recent tcpdump
issues (CAN-2005-1278, CAN-2005-1279, and CAN-2005-1280) I noticed
that there is another similar infinite loop DoS vulnerability in the
BGP handling code.
The problem lies in bgp_update_print() in print-bgp.c around line
1652, where the -1 return value from decode_prefix4() is not properly
This problem was fixed in tcpdump CVS repository in print-bgp.c
v. 1.95 on May 5, but it hasn't gone to the tcpdump 3.8 branch, and
hasn't been included in any of the vendor patch sets for earlier DoS
vulnerabilities that I have seen.
This issue should also affect RHEL2.1 and RHEL3
Created attachment 115005 [details]
Patch from upstream
Created attachment 115006 [details]
Proof of concept exploit
When will the embargo expire?
There is no set date yet. I'll let you know as soon as there is one.
I expect it to be soon. This fix is already in the upstream CVS, so
it makes little sense to try to keep it a secret for too long.
Removing embargo as per Simon Nielsen msg to vendor-sec
RHEL2.1 and RHEL3 aren't affected by this issue, the bug is only in
An advisory has been issued which should help the problem
described in this bug report. This report is therefore being
closed with a resolution of ERRATA. For more information
on the solution and/or where to find the updated files,
please follow the link below. You may reopen this bug report
if the solution does not work for you.