[SA18378] FreeBSD ipfw IP Fragment Denial of Service Vulnerability

TITLE:
FreeBSD ipfw IP Fragment Denial of Service Vulnerability

SECUNIA ADVISORY ID:
SA18378

VERIFY ADVISORY:
http://secunia.com/advisories/18378/

CRITICAL:
Moderately critical

IMPACT:
DoS

WHERE:
>From remote

OPERATING SYSTEM:
FreeBSD 6.x
http://secunia.com/product/6778/

DESCRIPTION:
A vulnerability has been reported in FreeBSD, which can be exploited
by malicious people to cause a DoS (Denial of Service).

The vulnerability is caused due to an error in the "ipfw" module when
handling IP fragments. This can be exploited to crash the firewall by
sending ICMP IP fragments to the firewall that match any of the
"reset", "reject" or "unreach" actions.

The vulnerability has been reported in FreeBSD 6.0-RELEASE.

SOLUTION:
Update FreeBSD or apply patch.

Fixed versions:
2006-01-11 08:02:16 UTC (RELENG_6, 6.0-STABLE)
2006-01-11 08:03:18 UTC (RELENG_6_0, 6.0-RELEASE-p2)

Patch for FreeBSD 6.0:
ftp://ftp.FreeBSD.org/pub/FreeBSD/CERT/patches/SA-06:04/ipfw.patch
ftp://ftp.FreeBSD.org/pub/FreeBSD/CERT/patches/SA-06:04/ipfw.patch.asc

PROVIDED AND/OR DISCOVERED BY:
Reported by vendor.

ORIGINAL ADVISORY:
ftp://ftp.freebsd.org/pub/FreeBSD/CERT/advisories/FreeBSD-SA-06:04.ipfw.asc

---

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