Slackware: kernel Privilege escalation vulnerability
Posted by LinuxSecurity.com Team   
Slackware A bounds-checking problem in the kernel's mremap() call could be used by a local attacker to gain root privileges.

[slackware-security]  Kernel security update  (SSA:2004-049-01)

New kernels are available for Slackware 9.1 and -current to fix
a bounds-checking problem in the kernel's mremap() call which
could be used by a local attacker to gain root privileges.
Please note that this is not the same issue as CAN-2003-0985
which was fixed in early January.

The kernels in Slackware 8.1 and 9.0 that were updated in
January are not vulnerable to this new issue because the patch
from Solar Designer that was used to fix the CAN-2003-0985 bugs
also happened to fix the problem that was discovered later.

Sites running Slackware 9.1 or -current should upgrade to a
new kernel.  After installing the new kernel, be sure to run
'lilo'.

More details about this issue may be found in the Common
Vulnerabilities and Exposures (CVE) database:

   http://cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2004-0077


Here are the details from the Slackware 9.1 ChangeLog:
+--------------------------+
Wed Feb 18 03:44:42 PST 2004
patches/kernels/:  Recompiled to fix another bounds-checking error in
  the kernel mremap() code.  (this is not the same issue that was fixed
  on Jan 6)  This bug could be used by a local attacker to gain root
  privileges.  Sites should upgrade to a new kernel.  After installing
  the new kernel, be sure to run 'lilo'.
    For more details, see:
     http://cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2004-0077
  Thanks to Paul Starzetz for finding and researching this issue.
  (* Security fix *)
patches/packages/kernel-ide-2.4.24-i486-2.tgz:  Patched, recompiled.
  (* Security fix *)
patches/packages/kernel-source-2.4.24-noarch-2.tgz:  Patched the kernel
  source with a fix for the mremap() problem from Solar Designer, and
  updated the Speakup driver (not pre-applied).
  (* Security fix *)
+--------------------------+


WHERE TO FIND THE NEW PACKAGES:
+-----------------------------+

Updated packages for Slackware 9.1: 
ftp://ftp.slackware.com/pub/slackware/slackware-9.1/patches/packages/kernel-ide-2.4.24-i486-2.tgz 
ftp://ftp.slackware.com/pub/slackware/slackware-9.1/patches/packages/kernel-source-2.4.24-noarch-2.tgz

An alternate kernel may be installed.  Those are found in this directory: 
ftp://ftp.slackware.com/pub/slackware/slackware-9.1/patches/kernels/


Updated packages for Slackware -current: 
ftp://ftp.slackware.com/pub/slackware/slackware-current/slackware/a/kernel-ide-2.4.24-i486-2.tgz 
ftp://ftp.slackware.com/pub/slackware/slackware-current/slackware/k/kernel-source-2.4.24-noarch-2.tgz 
ftp://ftp.slackware.com/pub/slackware/slackware-current/bootdisks/ 
ftp://ftp.slackware.com/pub/slackware/slackware-current/kernels/


MD5 SIGNATURES:
+-------------+

MD5 signatures may be downloaded from our FTP server:


Slackware 9.1 packages: 
ftp://ftp.slackware.com/pub/slackware/slackware-9.1/patches/CHECKSUMS.md5

To verify authenticity, this file has been signed with the Slackware
GPG key (use 'gpg --verify'):
 
ftp://ftp.slackware.com/pub/slackware/slackware-9.1/patches/CHECKSUMS.md5.asc


Slackware -current packages: 
ftp://ftp.slackware.com/pub/slackware/slackware-current/CHECKSUMS.md5 
ftp://ftp.slackware.com/pub/slackware/slackware-current/CHECKSUMS.md5.asc


INSTALLATION INSTRUCTIONS:
+------------------------+

Use upgradepkg to install the new kernel package.
After installing the kernel-ide package you will need to run lilo ('lilo' at
a command prompt) or create a new system boot disk ('makebootdisk'), and
reboot.

If desired, a kernel from the kernels/ directory may be used instead.  For
example, to use the kernel in kernels/scsi.s/, you would copy it to the
boot directory like this:

cd kernels/scsi.s
cp bzImage /boot/vmlinuz-scsi.s-2.4.24

Create a symbolic link:
ln -sf /boot/vmlinuz-scsi.s-2.4.24 /boot/vmlinuz

Then, run 'lilo' or create a new system boot disk and reboot.


+-----+

Slackware Linux Security Team 
http://slackware.com/gpg-key
security@slackware.com