Race condition in run_posix_cpu_timers in Linux kernel before 2.6.16.21 allows local users to cause a denial of service (BUG_ON crash) by causing one CPU to attach a timer to a process that is exiting.

A race condition was discovered in the do_add_counters() functions.
Processes which do not run with full root privileges, but have the CAP_NET_ADMIN capability can exploit this to crash the machine or read a random piece of kernel memory. In Ubuntu there are no packages that are affected by this, so this can only be an issue for you if you use third-party software that uses Linux capabilities. (CVE-2006-0039)

John Stultz discovered a faulty BUG_ON trigger in the handling of POSIX timers. A local attacker could exploit this to trigger a kernel oops and crash the machine. (CVE-2006-2445)

Dave Jones discovered that the PowerPC kernel did not perform certain required access_ok() checks. A local user could exploit this to read arbitrary kernel memory and crash the kernel on 64-bit systems, and possibly read arbitrary kernel memory on 32-bit systems.
(CVE-2006-2448)

A design flaw was discovered in the prctl(PR_SET_DUMPABLE, ...) system call, which allowed a local user to have core dumps created in a directory he could not normally write to. This could be exploited to drain available disk space on system partitions, or, under some circumstances, to execute arbitrary code with full root privileges.
This flaw only affects Ubuntu 6.06 LTS. (CVE-2006-2451)

In addition, the Ubuntu 6.06 LTS update fixes a range of bugs.

Note that Tenable Network Security has extracted the preceding description block directly from the Ubuntu security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

A number of vulnerabilities were discovered and corrected in the Linux 2.6 kernel :

The kernel did not clear sockaddr_in.sin_zero before returning IPv4 socket names for the getsockopt function, which could allow a local user to obtain portions of potentially sensitive memory if getsockopt() is called with SO_ORIGINAL_DST (CVE-2006-1343).

Prior to 2.6.16, a buffer overflow in the USB Gadget RNDIS implementation could allow a remote attacker to cause a Denial of Service via a remote NDIS response (CVE-2006-1368).

Prior to 2.6.13, local users could cause a Denial of Service (crash) via a dio transfer from the sg driver to memory mapped IO space (CVE-2006-1528).

Prior to and including 2.6.16, the kernel did not add the appropriate LSM file_permission hooks to the readv and writev functions, which could allow an attacker to bypass intended access restrictions (CVE-2006-1856).

Prior to 2.6.16.17, a buffer oveflow in SCTP could allow a remote attacker to cause a DoS (crash) and possibly execute arbitrary code via a malformed HB-ACK chunk (CVE-2006-1857).

Prior to 2.6.16.17, SCTP could allow a remote attacker to cause a DoS (crash) and possibly execute arbitrary code via a chunk length that is inconsistent with the actual length of provided parameters (CVE-2006-1858).

Prior to 2.6.16.16, a memory leak in fs/locks.c could allow an attacker to cause a DoS (memory consumption) via unspecified actions (CVE-2006-1859).

Prior to 2.6.16.16, lease_init in fs/locks.c could allow an attacker to cause a DoS (fcntl_setlease lockup) via certain actions (CVE-2006-1860).

Prior to 2.6.17, SCTP allowed remote attackers to cause a DoS (infinite recursion and crash) via a packet that contains two or more DATA fragments (CVE-2006-2274).

Prior to 2.6.16.21, a race condition in run_posix_cpu timers could allow a local user to cause a DoS (BUG_ON crash) by causing one CPU to attach a timer to a process that is exiting (CVE-2006-2445).

Prior to 2.6.17.1, xt_sctp in netfilter could allow an attacker to cause a DoS (infinite loop) via an SCTP chunk with a 0 length (CVE-2006-3085).

As well, an issue where IPC could hit an unmapped vmalloc page when near the page boundary has been corrected.

In addition to these security fixes, other fixes have been included such as :

  - avoid automatic update of kernel-source without updating     the kernel

    - fix USB EHCI handoff code, which made some machines       hang while booting

  - disable USB_BANDWIDTH which corrects a known problem in     some USB sound devices

  - fix a bluetooth refcounting bug which could hang the     machine

    - fix a NULL pointer dereference in USB-Serial's       serial_open() function

  - add missing wakeup in pl2303 TIOCMIWAIT handling

    - fix a possible user-after-free in USB-Serial core

    - suspend/resume fixes

    - HPET timer fixes

    - prevent fixed button event to reach userspace on S3       resume

    - add sysfs support in ide-tape

    - fix ASUS P5S800 reboot

Finally, a new drbd-utils package is provided that is a required upgrade with this new kernel due to a logic bug in the previously shipped version of drbd-utils that could cause a kernel panic on the master when a slave went offline.

The provided packages are patched to fix these vulnerabilities. All users are encouraged to upgrade to these updated kernels.

To update your kernel, please follow the directions located at :

http://www.mandriva.com/en/security/kernelupdate

ID	Name	Product	Family	Severity
27886	Ubuntu 5.04 / 5.10 / 6.06 LTS : linux-source-2.6.10/-2.6.12/-2.6.15 vulnerabilities (USN-311-1)	Nessus	Ubuntu Local Security Checks	medium
22058	Mandrake Linux Security Advisory : kernel (MDKSA-2006:123)	Nessus	Mandriva Local Security Checks	critical

Detections

Analytics

CVE-2006-2445

medium

Tenable Plugins

medium

critical