[SA18482] Linux Kernel Multiple Denial of Service Vulnerabilities

TITLE:
Linux Kernel Multiple Denial of Service Vulnerabilities

SECUNIA ADVISORY ID:
SA18482

VERIFY ADVISORY:
http://secunia.com/advisories/18482/

CRITICAL:
Moderately critical

IMPACT:
DoS

WHERE:
>From remote

OPERATING SYSTEM:
Linux Kernel 2.6.x
http://secunia.com/product/2719/

DESCRIPTION:
Some vulnerabilities have been reported in the Linux Kernel, which
can be exploited by malicious, local users and by malicious people to
cause a DoS (Denial of Service).

1) Missing validation of the "nlmsg_len" value in "netlink_rcv_skb()"
can cause an infinite loop. This can be exploited by local users to
cause a DoS by setting the value to 0.

2) An error in the PPTP NAT helper in the handling of inbound
PPTP_IN_CALL_REQUEST packets can cause an error in offset
calculation. This can be exploited to cause random memory corruption
and can crash the kernel.

3) An error exists in the PPTP NAT helper when calculating offsets
based on the difference between two pointers to the header. This can
result in the wrong offset being used, which can potentially crash
the kernel via illegal memory access.

SOLUTION:
Update to version 2.6.15.1.
http://kernel.org/

PROVIDED AND/OR DISCOVERED BY:
1) Martin Murray
2-3) Reported by vendor.

CHANGELOG:
http://kernel.org/pub/linux/kernel/v2.6/ChangeLog-2.6.15.1

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