(fwd) [Full-Disclosure] [SECURITY] [DSA-403-1] userland can access Linux kernel memory

[Arkadiusz Patyk]

On Mon, 1 Dec 2003 21:17:12 +0100,
debian-security-announce w lists.debian.org wrote:

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Debian Security Advisory DSA-403-1
security w debian.org
http://www.debian.org/security/                         Wichert
Akkerman
December  1, 2003
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Package        : kernel-image-2.4.18-1-alpha,
kernel-image-2.4.18-1-i386, kernel-source-2.4.18
Vulnerability  : userland can access full kernel memory 
Problem type   : local
Debian-specific: no
CVE Id(s)      : CAN-2003-0961

Recently multiple servers of the Debian project were compromised using
a
Debian developers account and an unknown root exploit. Forensics
revealed a burneye encrypted exploit. Robert van der Meulen managed to
decrypt the binary which revealed a kernel exploit. Study of the
exploit
by the RedHat and SuSE kernel and security teams quickly revealed that
the exploit used an integer overflow in the brk system call. Using
this bug it is possible for a userland program to trick the kernel
into
giving access to the full kernel address space. This problem was found
in September by Andrew Morton, but unfortunately that was too late for
the 2.4.22 kernel release.

This bug has been fixed in kernel version 2.4.23 for the 2.4 tree and
2.6.0-test6 kernel tree. For Debian it has been fixed in version
2.4.18-12 of the kernel source packages, version 2.4.18-14 of the i386
kernel images and version 2.4.18-11 of the alpha kernel images.

-- 
Arkadiusz Patyk [areq(at)pld-linux.org] [http://rescuecd.pld-linux.org/]
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