USN-103-1: Linux kernel vulnerabilities

1 April 2005

linux-source-2.6.8.1 vulnerabilities

A security issue affects these releases of Ubuntu and its derivatives:

  • Ubuntu 4.10

Software Description

Details

Mathieu Lafon discovered an information leak in the ext2 file system driver. When a new directory was created, the ext2 block written to disk was not initialized, so that previous memory contents (which could contain sensitive data like passwords) became visible on the raw device. This is particularly important if the target device is removable and thus can be read by users other than root. (CAN-2005-0400)

Yichen Xie discovered a Denial of Service vulnerability in the ELF loader. A specially crafted ELF library or executable could cause an attempt to free an invalid pointer, which lead to a kernel crash. (CAN-2005-0749)

Ilja van Sprundel discovered that the bluez_sock_create() function did not check its “protocol” argument for negative values. A local attacker could exploit this to execute arbitrary code with root privileges by creating a Bluetooth socket with a specially crafted protocol number. (CAN-2005-0750)

Michal Zalewski discovered that the iso9660 file system driver fails to check ranges properly in several cases. Mounting a specially crafted CD-ROM may have caused a buffer overflow leading to a kernel crash or even arbitrary code execution. (CAN-2005-0815)

Previous kernels did not restrict the use of the N_MOUSE line discipline in the serial driver. This allowed an unprivileged user to inject mouse movement and/or keystrokes (using the sunkbd driver) into the input subsystem, taking over the console or an X session, where another user is logged in. (CAN-2005-0839)

A Denial of Service vulnerability was found in the tmpfs driver, which is commonly used to mount RAM disks below /dev/shm and /tmp. The shm_nopage() did not properly verify its address argument, which could be exploited by a local user to cause a kernel crash with invalid addresses. (http://linux.bkbits.net:8080/linux-2.6/cset@420551fbRlv9-QG6Gw9Lw_bKVfPSsg)

Update instructions

The problem can be corrected by updating your system to the following package versions:

Ubuntu 4.10
linux-image-2.6.8.1-5-386
linux-image-2.6.8.1-5-686
linux-image-2.6.8.1-5-686-smp
linux-image-2.6.8.1-5-amd64-generic
linux-image-2.6.8.1-5-amd64-k8
linux-image-2.6.8.1-5-amd64-k8-smp
linux-image-2.6.8.1-5-amd64-xeon
linux-image-2.6.8.1-5-k7
linux-image-2.6.8.1-5-k7-smp
linux-image-2.6.8.1-5-power3
linux-image-2.6.8.1-5-power3-smp
linux-image-2.6.8.1-5-power4
linux-image-2.6.8.1-5-power4-smp
linux-image-2.6.8.1-5-powerpc
linux-image-2.6.8.1-5-powerpc-smp
linux-patch-debian-2.6.8.1

To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.

References