The MITRE CVE dictionary describes this issue as:
The X.25 implementation in the Linux kernel before 220.127.116.11 does not properly parse facilities, which allows remote attackers to cause a denial of service (heap memory corruption and panic) or possibly have unspecified other impact via malformed (1) X25_FAC_CALLING_AE or (2) X25_FAC_CALLED_AE data, related to net/x25/x25_facilities.c and net/x25/x25_in.c, a different vulnerability than CVE-2010-4164.
Find out more about CVE-2010-3873 from the
MITRE CVE dictionary dictionary and
This issue did not affect the version of Linux kernel as shipped with Red Hat
Enterprise Linux 3, 4, 5, and Red Hat Enterprise MRG as they did not include
support for CCITT X.25 Packet Layer.