Linux vulnerabilities

The Linux kernel 2.6.20 and 2.6.21 does not properly handle an invalid LDT segment selector in %cs (the xcs field) during ptrace single-step operations, which allows local users to cause a denial of service (NULL dereference and OOPS) via certain code that makes ptrace PTRACE_SETREGS and PTRACE_SINGLESTEP requests, related to the TRACE_IRQS_ON function, and possibly related to the arch_ptrace function.

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.

Linux kernel 2.4.35 and other versions allows local users to send arbitrary signals to a child process that is running at higher privileges by causing a setuid-root parent process to die, which delivers an attacker-controlled parent process death signal (PR_SET_PDEATHSIG).

The xfer_secondary_pool function in drivers/char/random.c in the Linux kernel 2.4 before 2.4.35 performs reseed operations on only the first few bytes of a buffer, which might make it easier for attackers to predict the output of the random number generator, related to incorrect use of the sizeof operator.

The drm/i915 component in the Linux kernel before 2.6.22.2, when used with i965G and later chipsets, allows local users with access to an X11 session and Direct Rendering Manager (DRM) to write to arbitrary memory locations and gain privileges via a crafted batchbuffer.

The Linux kernel before 2.6.23-rc1 checks the wrong global variable for the CIFS sec mount option, which might allow remote attackers to spoof CIFS network traffic that the client configured for security signatures, as demonstrated by lack of signing despite sec=ntlmv2i in a SetupAndX request.

Stack-based buffer overflow in the random number generator (RNG) implementation in the Linux kernel before 2.6.22 might allow local root users to cause a denial of service or gain privileges by setting the default wakeup threshold to a value greater than the output pool size, which triggers writing random numbers to the stack by the pool transfer function involving "bound check ordering". NOTE: this issue might only cross privilege boundaries in environments that have granular assignment of privileges for root.

The Distributed Lock Manager (DLM) in the cluster manager for Linux kernel 2.6.15 allows remote attackers to cause a denial of service (loss of lock services) by connecting to the DLM port, which probably prevents other processes from accessing the service.

The process scheduler in the Linux kernel 2.4 performs scheduling based on CPU billing gathered from periodic process sampling ticks, which allows local users to cause a denial of service (CPU consumption) by performing voluntary nanosecond sleeps that result in the process not being active during a clock interrupt, as described in "Secretly Monopolizing the CPU Without Superuser Privileges."

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."

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 decode_choice function in net/netfilter/nf_conntrack_h323_asn1.c in the Linux kernel before 2.6.20.15, 2.6.21.x before 2.6.21.6, and before 2.6.22 allows remote attackers to cause a denial of service (crash) via an encoded, out-of-range index value for a choice field, which triggers a NULL pointer dereference.

The lcd_write function in drivers/usb/misc/usblcd.c in the Linux kernel before 2.6.22-rc7 does not limit the amount of memory used by a caller, which allows local users to cause a denial of service (memory consumption).

The sysfs_readdir function in the Linux kernel 2.6, as used in Red Hat Enterprise Linux (RHEL) 4.5 and other distributions, allows users to cause a denial of service (kernel OOPS) by dereferencing a null pointer to an inode in a dentry.

The sctp_new function in (1) ip_conntrack_proto_sctp.c and (2) nf_conntrack_proto_sctp.c in Netfilter in Linux kernel 2.6 before 2.6.20.13, and 2.6.21.x before 2.6.21.4, allows remote attackers to cause a denial of service by causing certain invalid states that trigger a NULL pointer dereference.

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.

Integer underflow in the cpuset_tasks_read function in the Linux kernel before 2.6.20.13, and 2.6.21.x before 2.6.21.4, when the cpuset filesystem is mounted, allows local users to obtain kernel memory contents by using a large offset when reading the /dev/cpuset/tasks file.

The VFAT compat ioctls in the Linux kernel before 2.6.21.2, when run on a 64-bit system, allow local users to corrupt a kernel_dirent struct and cause a denial of service (system crash) via unknown vectors.

Unspecified vulnerability in drivers/crypto/geode-aes.c in GEODE-AES in the Linux kernel before 2.6.21.3 allows attackers to obtain sensitive information via unspecified vectors.

The embedded Linux kernel in certain Sun-Brocade SilkWorm switches before 20070516 does not properly handle a situation in which a non-root user creates a kernel process, which allows attackers to cause a denial of service (oops and device reboot) via unspecified vectors.

The compat_sys_mount function in fs/compat.c in Linux kernel 2.6.20 and earlier allows local users to cause a denial of service (NULL pointer dereference and oops) by mounting a smbfs file system in compatibility mode ("mount -t smbfs").

Memory leak in the PPP over Ethernet (PPPoE) socket implementation in the Linux kernel before 2.6.21-git8 allows local users to cause a denial of service (memory consumption) by creating a socket using connect, and releasing it before the PPPIOCGCHAN ioctl is initialized.

The nl_fib_lookup function in net/ipv4/fib_frontend.c in Linux Kernel before 2.6.20.8 allows attackers to cause a denial of service (kernel panic) via NETLINK_FIB_LOOKUP replies, which trigger infinite recursion and a stack overflow.

The _udp_lib_get_port function in net/ipv4/udp.c in Linux kernel 2.6.21 and earlier does not prevent a bind to a port with a local address when there is already a bind to that port with a wildcard local address, which might allow local users to intercept local traffic for daemons or other applications.

The utrace support in Linux kernel 2.6.18, and other versions, allows local users to cause a denial of service (system hang) related to "MT exec + utrace_attach spin failure mode," as demonstrated by ptrace-thrash.c.

The setsockopt function in the L2CAP and HCI Bluetooth support in the Linux kernel before 2.4.34.3 allows context-dependent attackers to read kernel memory and obtain sensitive information via unspecified vectors involving the copy_from_user function accessing an uninitialized stack buffer.

A typo in Linux kernel 2.6 before 2.6.21-rc6 and 2.4 before 2.4.35 causes RTA_MAX to be used as an array size instead of RTN_MAX, which leads to an "out of bound access" by the (1) dn_fib_props (dn_fib.c, DECNet) and (2) fib_props (fib_semantics.c, IPv4) functions.

The atalk_sum_skb function in AppleTalk for Linux kernel 2.6.x before 2.6.21, and possibly 2.4.x, allows remote attackers to cause a denial of service (crash) via an AppleTalk frame that is shorter than the specified length, which triggers a BUG_ON call when an attempt is made to perform a checksum.

The DCCP support in the do_dccp_getsockopt function in net/dccp/proto.c in Linux kernel 2.6.20 and later does not verify the upper bounds of the optlen value, which allows local users running on certain architectures to read kernel memory or cause a denial of service (oops), a related issue to CVE-2007-1730.

Integer signedness error in the DCCP support in the do_dccp_getsockopt function in net/dccp/proto.c in Linux kernel 2.6.20 and later allows local users to read kernel memory or cause a denial of service (oops) via a negative optlen value.

net/ipv6/tcp_ipv6.c in Linux kernel 2.6.x up to 2.6.21-rc3 inadvertently copies the ipv6_fl_socklist from a listening TCP socket to child sockets, which allows local users to cause a denial of service (OOPS) or double free by opening a listening IPv6 socket, attaching a flow label, and connecting to that socket.

nf_conntrack in netfilter in the Linux kernel before 2.6.20.3 does not set nfctinfo during reassembly of fragmented packets, which leaves the default value as IP_CT_ESTABLISHED and might allow remote attackers to bypass certain rulesets using IPv6 fragments.

nfnetlink_log in netfilter in the Linux kernel before 2.6.20.3 allows attackers to cause a denial of service (crash) via unspecified vectors involving the (1) nfulnl_recv_config function, (2) using "multiple packets per netlink message", and (3) bridged packets, which trigger a NULL pointer dereference.

The ipv6_getsockopt_sticky function in net/ipv6/ipv6_sockglue.c in the Linux kernel before 2.6.20.2 allows local users to read arbitrary kernel memory via certain getsockopt calls that trigger a NULL dereference.

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.

Buffer overflow in the bufprint function in capiutil.c in libcapi, as used in Linux kernel 2.6.9 to 2.6.20 and isdn4k-utils, allows local users to cause a denial of service (crash) and possibly gain privileges via a crafted CAPI packet.

The sys_timer_create function in posix-timers.c for Linux kernel 2.6.x allows local users to cause a denial of service (memory consumption) and possibly bypass memory limits or cause other processes to be killed by creating a large number of posix timers, which are allocated in kernel memory but are not treated as part of the process' memory.

The Linux kernel 2.6.13 and other versions before 2.6.20.1 allows remote attackers to cause a denial of service (oops) via a crafted NFSACL 2 ACCESS request that triggers a free of an incorrect pointer.

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.

umount, when running with the Linux 2.6.15 kernel on Slackware Linux 10.2, allows local users to trigger a NULL dereference and application crash by invoking the program with a pathname for a USB pen drive that was mounted and then physically removed, which might allow the users to obtain sensitive information, including core file contents.

The key serial number collision avoidance code in the key_alloc_serial function in Linux kernel 2.6.9 up to 2.6.20 allows local users to cause a denial of service (crash) via vectors that trigger a null dereference, as originally reported as "spinlock CPU recursion."

The dev_queue_xmit function in Linux kernel 2.6 can fail before calling the local_bh_disable function, which could lead to data corruption and "node lockups." NOTE: it is not clear whether this issue is exploitable.

The aio_setup_ring function in Linux kernel does not properly initialize a variable, which allows local users to cause a denial of service (crash) via an unspecified error path that causes an incorrect free operation.

Unspecified vulnerability in the listxattr system call in Linux kernel, when a "bad inode" is present, allows local users to cause a denial of service (data corruption) and possibly gain privileges via unknown vectors.

Unspecified versions of the Linux kernel allow local users to cause a denial of service (unrecoverable zombie process) via a program with certain instructions that prevent init from properly reaping a child whose parent has died.

Linux kernel before 2.6.18, when running on x86_64 systems, does not properly save or restore EFLAGS during a context switch, which allows local users to cause a denial of service (crash) by causing SYSENTER to set an NT flag, which can trigger a crash on the IRET of the next task.

The isdn_ppp_ccp_reset_alloc_state function in drivers/isdn/isdn_ppp.c in the Linux 2.4 kernel before 2.4.34-rc4 does not call the init_timer function for the ISDN PPP CCP reset state timer, which has unknown attack vectors and results in a system crash.

The mincore function in the Linux kernel before 2.4.33.6 does not properly lock access to user space, which has unspecified impact and attack vectors, possibly related to a deadlock.

Multiple buffer overflows in the cmtp_recv_interopmsg function in the Bluetooth driver (net/bluetooth/cmtp/capi.c) in the Linux kernel 2.4.22 up to 2.4.33.4 and 2.6.2 before 2.6.18.6, and 2.6.19.x, allow remote attackers to cause a denial of service (crash) and possibly execute arbitrary code via CAPI messages with a large value for the length of the (1) manu (manufacturer) or (2) serial (serial number) field.

The do_coredump function in fs/exec.c in the Linux kernel 2.6.19 sets the flag variable to O_EXCL but does not use it, which allows context-dependent attackers to modify arbitrary files via a rewrite attack during a core dump.