7.8 - RHSA-2005:366

Problem Description:

Updated kernel packages that fix several security issues are now available for Red Hat Enterprise Linux 4.

This update has been rated as having important security impact by the Red Hat Security Response Team.

The Linux kernel handles the basic functions of the operating system.

2. Relevant releases/architectures:

Red Hat Enterprise Linux AS version 4 - i386, ia64, noarch, ppc, s390, s390x, x86_64 Red Hat Enterprise Linux Desktop version 4 - i386, noarch, x86_64 Red Hat Enterprise Linux ES version 4 - i386, ia64, noarch, x86_64 Red Hat Enterprise Linux WS version 4 - i386, ia64, noarch, x86_64

3. Problem description:

A flaw in the fib_seq_start function was discovered. A local user could use this flaw to cause a denial of service (system crash) via /proc/net/route. (CAN-2005-1041)

A flaw in the tmpfs file system was discovered. A local user could use this flaw to cause a denial of service (system crash). (CAN-2005-0977)

An integer overflow flaw was found when writing to a sysfs file. A local user could use this flaw to overwrite kernel memory, causing a denial of service (system crash) or arbitrary code execution. (CAN-2005-0867)

Keith Owens reported a flaw in the Itanium unw_unwind_to_user function. A local user could use this flaw to cause a denial of service (system crash) on Itanium architectures. (CAN-2005-0135)

A flaw in the NFS client O_DIRECT error case handling was discovered. A local user could use this flaw to cause a denial of service (system crash). (CAN-2005-0207)

A flaw in fragment forwarding was discovered that affected the netfilter subsystem for certain network interface cards. A remote attacker could send a set of bad fragments and cause a denial of service (system crash). Acenic and SunGEM network interfaces were the only adapters affected, which are in widespread use. (CAN-2005-0209)

A flaw was discovered in the Linux PPP driver. On systems allowing remote users to connect to a server using ppp, a remote client could cause a denial of service (system crash). (CAN-2005-0384)

A flaw was discovered in the ext2 file system code. When a new directory is created, the ext2 block written to disk is not initialized, which could lead to an information leak if a disk image is made available to unprivileged users. (CAN-2005-0400)

A flaw in fragment queuing was discovered that affected the Linux kernel netfilter subsystem. On systems configured to filter or process network packets (e.g. firewalling), a remote attacker could send a carefully crafted set of fragmented packets to a machine and cause a denial of service (system crash). In order to sucessfully exploit this flaw, the attacker would need to know or guess some aspects of the firewall ruleset on the target system. (CAN-2005-0449)

A number of flaws were found in the Linux 2.6 kernel. A local user could use these flaws to read kernel memory or cause a denial of service (crash). (CAN-2005-0529, CAN-2005-0530, CAN-2005-0531)

An integer overflow in sys_epoll_wait in eventpoll.c was discovered. A local user could use this flaw to overwrite low kernel memory. This memory is usually unused, not usually resulting in a security consequence. (CAN-2005-0736)

A flaw when freeing a pointer in load_elf_library was discovered. A local user could potentially use this flaw to cause a denial of service (crash). (CAN-2005-0749)

A flaw was discovered in the bluetooth driver system. On systems where the bluetooth modules are loaded, a local user could use this flaw to gain elevated (root) privileges. (CAN-2005-0750)

A race condition was discovered that affected the Radeon DRI driver. A local user who has DRI privileges on a Radeon graphics card may be able to use this flaw to gain root privileges. (CAN-2005-0767)

Multiple range checking flaws were discovered in the iso9660 file system handler. An attacker could create a malicious file system image which would cause a denial or service or potentially execute arbitrary code if mounted. (CAN-2005-0815)

A flaw was discovered when setting line discipline on a serial tty. A local user may be able to use this flaw to inject mouse movements or keystrokes when another user is logged in. (CAN-2005-0839)

Red Hat Enterprise Linux 4 users are advised to upgrade their kernels to the packages associated with their machine architectures and configurations as listed in this erratum.

Please note that a vulnerability addressed by this update (CAN-2005-0449) required a change to the kernel module ABI which could cause third party modules to not work. However, Red Hat is currently not aware of any module that would be affected by this change.

4. Solution:

Before applying this update, make sure that all previously-released errata relevant to your system have been applied. Use Red Hat Network to download and update your packages. To launch the Red Hat Update Agent, use the following command:

up2date

For information on how to install packages manually, refer to the following Web page for the System Administration or Customization guide specific to your system:

http://www.redhat.com/docs/manuals/enterprise/

5. Bug IDs fixed (http://bugzilla.redhat.com/):

147468 - CAN-2005-0449 Possible remote Oops/firewall bypass 148868 - CAN-2005-0135 ia64 local DoS 148878 - CAN-2005-0207 nfs client O_DIRECT oops 149466 - CAN-2005-0529 Sign handling issues on v2.6 (CAN-2005-0530 CAN-2005-0531) 149589 - CAN-2005-0209 netfilter SKB problem 151240 - CAN-2005-0384 pppd remote DoS 151249 - CAN-2005-0736 epoll overflow 151902 - CAN-2005-0767 drm race in radeon 152177 - CAN-2005-0750 bluetooth security flaw 152399 - CAN-2005-0400 ext2 mkdir() directory entry random kernel memory leak 152405 - CAN-2005-0815 isofs range checking flaws 152410 - CAN-2005-0749 load_elf_library possible DoS 152417 - CAN-2005-0839 N_MOUSE line discipline flaw 152561 - CAN-2005-0977 tmpfs truncate bug 154219 - CAN-2005-0867 sysfs signedness problem 154551 - CAN-2005-1041 crash while reading /proc/net/route