Linux Kernel 2.6.16

The selinux_ip_postroute_iptables_compat function in security/selinux/hooks.c in the SELinux subsystem in the Linux kernel before 2.6.27.22, and 2.6.28.x before 2.6.28.10, when compat_net is enabled, omits calls to avc_has_perm for the (1) node and (2) port, which allows local users to bypass intended restrictions on network traffic. NOTE: this was incorrectly reported as an issue fixed in 2.6.27.21.

Race condition in Linux kernel 2.6.15 to 2.6.17, when running on SMP platforms, allows local users to cause a denial of service (crash) by creating and exiting a large number of tasks, then accessing the /proc entry of a task that is exiting, which causes memory corruption that leads to a failure in the prune_dcache function or a BUG_ON error in include/linux/list.h.

The minix filesystem code in Linux kernel 2.6.x before 2.6.24, including 2.6.18, allows local users to cause a denial of service (hang) via a malformed minix file stream that triggers an infinite loop in the minix_bmap function. NOTE: this issue might be due to an integer overflow or signedness error.

The ext2 file system code in Linux kernel 2.6.x allows local users to cause a denial of service (crash) via an ext2 stream with malformed data structures that triggers an error in the ext2_check_page due to a length that is smaller than the minimum.

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.

The zlib_inflate function in Linux kernel 2.6.x allows local users to cause a denial of service (crash) via a malformed filesystem that uses zlib compression that triggers memory corruption, as demonstrated using cramfs.

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.

madvise_remove in Linux kernel 2.6.16 up to 2.6.16.6 does not follow file and mmap restrictions, which allows local users to bypass IPC permissions and replace portions of readonly tmpfs files with zeroes, aka the MADV_REMOVE vulnerability. NOTE: this description was originally written in a way that combined two separate issues. The mprotect issue now has a separate name, CVE-2006-2071.

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 sock_getsockopt function in net/core/sock.c in the Linux kernel before 2.6.28.6 does not initialize a certain structure member, which allows local users to obtain potentially sensitive information from kernel memory via an SO_BSDCOMPAT getsockopt request.

The clone system call in the Linux kernel 2.6.28 and earlier allows local users to send arbitrary signals to a parent process from an unprivileged child process by launching an additional child process with the CLONE_PARENT flag, and then letting this new process exit.

Linux kernel 2.6.17, and other versions before 2.6.22, does not check when a user attempts to set RLIMIT_CPU to 0 until after the change is made, which allows local users to bypass intended resource limits.

The Linux kernel before 2.6.16.9 and the FreeBSD kernel, when running on AMD64 and other 7th and 8th generation AuthenticAMD processors, only save/restore the FOP, FIP, and FDP x87 registers in FXSAVE/FXRSTOR when an exception is pending, which allows one process to determine portions of the state of floating point instructions of other processes, which can be leveraged to obtain sensitive information such as cryptographic keys. NOTE: this is the documented behavior of AMD64 processors, but it is inconsistent with Intel processors in a security-relevant fashion that was not addressed by the kernels.

The copy_from_user function in the uaccess code in Linux kernel 2.6 before 2.6.19-rc1, when running on s390, does not properly clear a kernel buffer, which allows local user space programs to read portions of kernel memory by "appending to a file from a bad address," which triggers a fault that prevents the unused memory from being cleared in the kernel buffer.

The selinux_ptrace logic in hooks.c in SELinux for Linux 2.6.6 allows local users with ptrace permissions to change the tracer SID to an SID of another process.

The seqfile handling (ip6fl_get_n function in ip6_flowlabel.c) in Linux kernel 2.6 up to 2.6.18-stable allows local users to cause a denial of service (hang or oops) via unspecified manipulations that trigger an infinite loop while searching for flowlabels.

Linux kernel 2.4.x and 2.6.x up to 2.6.16 allows local users to bypass IPC permissions and modify a readonly attachment of shared memory by using mprotect to give write permission to the attachment. NOTE: some original raw sources combined this issue with CVE-2006-1524, but they are different bugs.

Linux kernel 2.6.x before 2.6.20 allows local users to read unreadable binaries by using the interpreter (PT_INTERP) functionality and triggering a core dump, a variant of CVE-2004-1073.

The skfp_ioctl function in drivers/net/skfp/skfddi.c in the Linux kernel before 2.6.28.6 permits SKFP_CLR_STATS requests only when the CAP_NET_ADMIN capability is absent, instead of when this capability is present, which allows local users to reset the driver statistics, related to an "inverted logic" issue.

net/bridge/netfilter/ebtables.c in the ebtables module in the netfilter framework in the Linux kernel before 2.6.33-rc4 does not require the CAP_NET_ADMIN capability for setting or modifying rules, which allows local users to bypass intended access restrictions and configure arbitrary network-traffic filtering via a modified ebtables application.

The signal handling in the Linux kernel before 2.6.22, including 2.6.2, when running on PowerPC systems using HTX, allows local users to cause a denial of service via unspecified vectors involving floating point corruption and concurrency, related to clearing of MSR bits.

The wake_futex_pi function in kernel/futex.c in the Linux kernel before 2.6.33-rc7 does not properly handle certain unlock operations for a Priority Inheritance (PI) futex, which allows local users to cause a denial of service (OOPS) and possibly have unspecified other impact via vectors involving modification of the futex value from user space.

net/ipv4/netfilter/arp_tables.c in the IPv4 implementation in the Linux kernel before 2.6.39 does not place the expected '\0' character at the end of string data in the values of certain structure members, which allows local users to obtain potentially sensitive information from kernel memory by leveraging the CAP_NET_ADMIN capability to issue a crafted request, and then reading the argument to the resulting modprobe process.

net/ipv4/netfilter/ip_tables.c in the IPv4 implementation in the Linux kernel before 2.6.39 does not place the expected '\0' character at the end of string data in the values of certain structure members, which allows local users to obtain potentially sensitive information from kernel memory by leveraging the CAP_NET_ADMIN capability to issue a crafted request, and then reading the argument to the resulting modprobe process.

net/ipv6/netfilter/ip6_tables.c in the IPv6 implementation in the Linux kernel before 2.6.39 does not place the expected '\0' character at the end of string data in the values of certain structure members, which allows local users to obtain potentially sensitive information from kernel memory by leveraging the CAP_NET_ADMIN capability to issue a crafted request, and then reading the argument to the resulting modprobe process.

Software suspend 2 2-2.2.1, when used with the Linux kernel 2.6.16, stores pre-boot authentication passwords in the BIOS Keyboard buffer and does not clear this buffer after use, which allows local users to obtain sensitive information by reading the physical memory locations associated with this buffer.

The proc_oom_score function in fs/proc/base.c in the Linux kernel before 2.6.34-rc4 uses inappropriate data structures during selection of a candidate for the OOM killer, which might allow local users to cause a denial of service via unspecified patterns of task creation.

The do_task_stat function in fs/proc/array.c in the Linux kernel before 2.6.39-rc1 does not perform an expected uid check, which makes it easier for local users to defeat the ASLR protection mechanism by reading the start_code and end_code fields in the /proc/#####/stat file for a process executing a PIE binary.

The process scheduler in the Linux kernel 2.6.16 gives preference to "interactive" processes that perform voluntary sleeps, which allows local users to cause a denial of service (CPU consumption), as described in "Secretly Monopolizing the CPU Without Superuser Privileges."

Race condition in the __find_get_block_slow function in the ISO9660 filesystem in Linux 2.6.18 and possibly other versions allows local users to cause a denial of service (infinite loop) by mounting a crafted ISO9660 filesystem containing malformed data structures.

The random number feature in Linux kernel 2.6 before 2.6.20.13, and 2.6.21.x before 2.6.21.4, (1) does not properly seed pools when there is no entropy, or (2) uses an incorrect cast when extracting entropy, which might cause the random number generator to provide the same values after reboots on systems without an entropy source.

mm/shmem.c in the Linux kernel before 2.6.28-rc8, when strict overcommit is enabled and CONFIG_SECURITY is disabled, does not properly handle the export of shmemfs objects by knfsd, which allows attackers to cause a denial of service (NULL pointer dereference and knfsd crash) or possibly have unspecified other impact via unknown vectors. NOTE: this vulnerability exists because of an incomplete fix for CVE-2010-1643.