Linux Kernel 2.6.18

The kill_something_info function in kernel/signal.c in the Linux kernel before 2.6.28 does not consider PID namespaces when processing signals directed to PID -1, which allows local users to bypass the intended namespace isolation, and send arbitrary signals to all processes in all namespaces, via a kill command.

The do_splice_from function in fs/splice.c in the Linux kernel before 2.6.27 does not reject file descriptors that have the O_APPEND flag set, which allows local users to bypass append mode and make arbitrary changes to other locations in the file.

arch/i386/kernel/sysenter.c in the Virtual Dynamic Shared Objects (vDSO) implementation in the Linux kernel before 2.6.21 does not properly check boundaries, which allows local users to gain privileges or cause a denial of service via unspecified vectors, related to the install_special_mapping, syscall, and syscall32_nopage functions.

The get_instantiation_keyring function in security/keys/keyctl.c in the KEYS subsystem in the Linux kernel before 2.6.32-rc5 does not properly maintain the reference count of a keyring, which allows local users to gain privileges or cause a denial of service (OOPS) via vectors involving calls to this function without specifying a keyring by ID, as demonstrated by a series of keyctl request2 and keyctl list commands.

The exit_notify function in kernel/exit.c in the Linux kernel before 2.6.30-rc1 does not restrict exit signals when the CAP_KILL capability is held, which allows local users to send an arbitrary signal to a process by running a program that modifies the exit_signal field and then uses an exec system call to launch a setuid application.

The do_ipv6_setsockopt function in net/ipv6/ipv6_sockglue.c in Linux kernel before 2.6.20, and possibly other versions, allows local users to cause a denial of service (oops) by calling setsockopt with the IPV6_RTHDR option name and possibly a zero option length or invalid option value, which triggers a NULL pointer dereference.

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.

The CIFS filesystem in the Linux kernel before 2.6.22, when Unix extension support is enabled, does not honor the umask of a process, which allows local users to gain privileges.

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.

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.

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.

Race condition in the do_setlk function in fs/nfs/file.c in the Linux kernel before 2.6.26 allows local users to cause a denial of service (crash) via vectors resulting in an interrupted RPC call that leads to a stray FL_POSIX lock, related to improper handling of a race between fcntl and close in the EINTR case.

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 MMIO instruction decoder in the Xen hypervisor in the Linux kernel 2.6.18 in Red Hat Enterprise Linux (RHEL) 5 allows guest OS users to cause a denial of service (32-bit guest OS crash) via vectors that trigger an unspecified instruction emulation.

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 ReiserFS functionality in Linux kernel 2.6.18, and possibly other versions, allows local users to cause a denial of service via a malformed ReiserFS file system that triggers memory corruption when a sync is performed.

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 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.

drivers/xen/usbback/usbback.c in linux-2.6.18-xen-3.4.0 (aka the Xen 3.4.x support patches for the Linux kernel 2.6.18), as used in the Linux kernel 2.6.x and 3.x in SUSE Linux distributions, allows guest OS users to obtain sensitive information from uninitialized locations in host OS kernel memory via unspecified vectors.

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.

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.

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/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/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.

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.

A certain Red Hat configuration step for the qla2xxx driver in the Linux kernel 2.6.18 on Red Hat Enterprise Linux (RHEL) 5, when N_Port ID Virtualization (NPIV) hardware is used, sets world-writable permissions for the (1) vport_create and (2) vport_delete files under /sys/class/scsi_host/, which allows local users to make arbitrary changes to SCSI host attributes by modifying these files.

libata in the Linux kernel before 2.6.27.9 does not set minimum timeouts for SG_IO requests, which allows local users to cause a denial of service (Programmed I/O mode on drives) via multiple simultaneous invocations of an unspecified test program.

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.