Some vulnerabilities have been reported in the Linux kernel. The first has an unknown impact, the others can be exploited by malicious, local users to cause a DoS (Denial of Service), or by malicious people to bypass certain security restrictions.

1) An error exists in the handling of access to ar.rsc via ptrace and restore_sigcontext.

2) An error in the delivery of signals can cause a kernel panic when a sub-thread "exec" with a pending timer.

3) An error in "ptrace()" when processing specially crafted addresses on the AMD64 platform can cause the kernel to crash.

Vulnerability #1, #2, and #3 has been reported in the 2.6 kernel branch.

4) An error in the stack segment fault handler in "/arch/x86_64/kernel/traps.c" may be exploited to crash the kernel via a stack fault exception.

The vulnerability has been reported in both 2.4 and 2.6 kernel branches.

5) An off-by one quadword error in "/x86_64/kernel/ptrace.c" can potentially be exploited to crash the kernel by writing a word 40 bytes into the page above the kernel stack of a process.

6) An error in "mm/ioremap.c" on the x86_64 platform may be exploited by local users to cause a denial of service or to disclose certain information by performing an "iremap" on certain memory maps that causes a lookup of a page that does not exist.

7) The HFS and HFS+ file system drivers do not properly verify that the file system to be mounted is really HFS/HFS+. This may be exploited by users who can mount file systems to crash the kernel by using hfsplus to mount a filesystem that is not hfsplus.

8) It is possible to poison the bridge forwarding table by frames that have been dropped by filtering. This may be exploited to cause the bridge to forward packets with spoofed source addresses.

Vulnerability #5, #6, #7 and #8 has been reported in the 2.6 kernel branch.

Solution
Update to version 2.6.12.1.
Further details available in Customer Area

Provided and/or discovered by
1-4) Reported by vendor.
5) John Blackwood

Changelog
Further details available in Customer Area

Original Advisory
Kernel.org:
http://kernel.org/pub/linux/kernel/v2.6/ChangeLog-2.6.12.1
http://kernel.org/pub/linux/kernel/v2.6/ChangeLog-2.6.12
http://www.kernel.org/pub/linux/kernel/v2.4/testing/patch-2.4.32.log

Deep Links
Links available in Customer Area