Race condition in the ptrace and utrace support in the Linux kernel 2.6.9 through 2.6.25, as used in Red Hat Enterprise Linux (RHEL) 4, allows local users to cause a denial of service (oops) via a long series of PTRACE_ATTACH ptrace calls to another user's process that trigger a conflict between utrace_detach and report_quiescent, related to "late ptrace_may_attach() check" and "race around &dead_engine_ops setting," a different vulnerability than CVE-2007-0771 and CVE-2008-1514. NOTE: this issue might only affect kernel versions before 2.6.16.x.

The pppol2tp_recvmsg function in drivers/net/pppol2tp.c in the Linux kernel 2.6 before 2.6.26-rc6 allows remote attackers to cause a denial of service (kernel heap memory corruption and system crash) and possibly have unspecified other impact via a crafted PPPOL2TP packet that results in a large value for a certain length variable.

The asn1 implementation in (a) the Linux kernel 2.4 before 2.4.36.6 and 2.6 before 2.6.25.5, as used in the cifs and ip_nat_snmp_basic modules; and (b) the gxsnmp package; does not properly validate length values during decoding of ASN.1 BER data, which allows remote attackers to cause a denial of service (crash) or execute arbitrary code via (1) a length greater than the working buffer, which can lead to an unspecified overflow; (2) an oid length of zero, which can lead to an off-by-one error; or (3) an indefinite length for a primitive encoding.

The (1) sparc_mmap_check function in arch/sparc/kernel/sys_sparc.c and the (2) sparc64_mmap_check function in arch/sparc64/kernel/sys_sparc.c, in the Linux kernel 2.4 before 2.4.36.5 and 2.6 before 2.6.25.3, omit some virtual-address range (aka span) checks when the mmap MAP_FIXED bit is not set, which allows local users to cause a denial of service (panic) via unspecified mmap calls.

Linux kernel before 2.6.25.2 does not apply a certain protection mechanism for fcntl functionality, which allows local users to (1) execute code in parallel or (2) exploit a race condition to obtain "re-ordered access to the descriptor table."

The bdx_ioctl_priv function in the tehuti driver (tehuti.c) in Linux kernel 2.6.x before 2.6.25.1 does not properly check certain information related to register size, which has unspecified impact and local attack vectors, probably related to reading or writing kernel memory.

arch/s390/kernel/ptrace.c in Linux kernel 2.6.9, and other versions before 2.6.27-rc6, on s390 platforms allows local users to cause a denial of service (kernel panic) via the user-area-padding test from the ptrace testsuite in 31-bit mode, which triggers an invalid dereference.

The chrp_show_cpuinfo function (chrp/setup.c) in Linux kernel 2.4.21 through 2.6.18-53, when running on PowerPC, might allow local users to cause a denial of service (crash) via unknown vectors that cause the of_get_property function to fail, which triggers a NULL pointer dereference.

VFS in the Linux kernel before 2.6.22.16, and 2.6.23.x before 2.6.23.14, performs tests of access mode by using the flag variable instead of the acc_mode variable, which might allow local users to bypass intended permissions and remove directories.

The disconnect method in the Philips USB Webcam (pwc) driver in Linux kernel 2.6.x before 2.6.22.6 "relies on user space to close the device," which allows user-assisted local attackers to cause a denial of service (USB subsystem hang and CPU consumption in khubd) by not closing the device after the disconnect is invoked. NOTE: this rarely crosses privilege boundaries, unless the attacker can convince the victim to unplug the affected device.