The VT implementation (vt_ioctl.c) in Linux kernel 2.6.12, and possibly other versions including 2.6.14.4, allows local users to use the KDSKBSENT ioctl on terminals of other users and gain privileges, as demonstrated by modifying key bindings using loadkeys.

The original update lacked recompiled ALSA modules against the new  kernel ABI. Furthermore, kernel-latest-2.4-sparc now correctly  depends on the updated packages. For completeness we're providing the  original problem description :

  Several local and remote vulnerabilities have been discovered in the   Linux kernel that may lead to a denial of service or the execution   of arbitrary code. The Common Vulnerabilities and Exposures project   identifies the following problems :

    - CVE-2004-0887       Martin Schwidefsky discovered that the privileged       instruction SACF (Set Address Space Control Fast) on       the S/390 platform is not handled properly, allowing       for a local user to gain root privileges.

    - CVE-2004-1058       A race condition allows for a local user to read the       environment variables of another process that is still       spawning through /proc/.../cmdline.

    - CVE-2004-2607       A numeric casting discrepancy in sdla_xfer allows       local users to read portions of kernel memory via a       large len argument which is received as an int but       cast to a short, preventing read loop from filling a       buffer.

    - CVE-2005-0449       An error in the skb_checksum_help() function from the       netfilter framework has been discovered that allows       the bypass of packet filter rules or a denial of       service attack.

    - CVE-2005-1761       A vulnerability in the ptrace subsystem of the IA-64       architecture can allow local attackers to overwrite       kernel memory and crash the kernel.

    - CVE-2005-2457       Tim Yamin discovered that insufficient input       validation in the compressed ISO file system (zisofs)       allows a denial of service attack through maliciously       crafted ISO images.

    - CVE-2005-2555       Herbert Xu discovered that the setsockopt() function       was not restricted to users/processes with the       CAP_NET_ADMIN capability. This allows attackers to       manipulate IPSEC policies or initiate a denial of       service attack.

    - CVE-2005-2709       Al Viro discovered a race condition in the /proc       handling of network devices. A (local) attacker could       exploit the stale reference after interface shutdown       to cause a denial of service or possibly execute code       in kernel mode.

    - CVE-2005-2973       Tetsuo Handa discovered that the udp_v6_get_port()       function from the IPv6 code can be forced into an       endless loop, which allows a denial of service attack.

    - CVE-2005-3257       Rudolf Polzer discovered that the kernel improperly       restricts access to the KDSKBSENT ioctl, which can       possibly lead to privilege escalation.

    - CVE-2005-3783       The ptrace code using CLONE_THREAD didn't use the       thread group ID to determine whether the caller is       attaching to itself, which allows a denial of service       attack.

    - CVE-2005-3806       Yen Zheng discovered that the IPv6 flow label code       modified an incorrect variable, which could lead to       memory corruption and denial of service.

    - CVE-2005-3848       Ollie Wild discovered a memory leak in the       icmp_push_reply() function, which allows denial of       service through memory consumption.

    - CVE-2005-3857       Chris Wright discovered that excessive allocation of       broken file lock leases in the VFS layer can exhaust       memory and fill up the system logging, which allows       denial of service.

    - CVE-2005-3858       Patrick McHardy discovered a memory leak in the       ip6_input_finish() function from the IPv6 code, which       allows denial of service.

    - CVE-2005-4618       Yi Ying discovered that sysctl does not properly       enforce the size of a buffer, which allows a denial of       service attack.

Several local and remote vulnerabilities have been discovered in the Linux kernel that may lead to a denial of service or the execution of arbitrary code. The Common Vulnerabilities and Exposures project identifies the following problems :

  - CVE-2004-1017     Multiple overflows exist in the io_edgeport driver which     might be usable as a denial of service attack vector.

  - CVE-2005-0124     Bryan Fulton reported a bounds checking bug in the     coda_pioctl function which may allow local users to     execute arbitrary code or trigger a denial of service     attack.

  - CVE-2005-0449     An error in the skb_checksum_help() function from the     netfilter framework has been discovered that allows the     bypass of packet filter rules or a denial of service     attack.

  - CVE-2005-2457     Tim Yamin discovered that insufficient input validation     in the zisofs driver for compressed ISO file systems     allows a denial of service attack through maliciously     crafted ISO images.

  - CVE-2005-2490     A buffer overflow in the sendmsg() function allows local     users to execute arbitrary code.

  - CVE-2005-2555     Herbert Xu discovered that the setsockopt() function was     not restricted to users/processes with the CAP_NET_ADMIN     capability. This allows attackers to manipulate IPSEC     policies or initiate a denial of service attack. 

  - CVE-2005-2709     Al Viro discovered a race condition in the /proc     handling of network devices. A (local) attacker could     exploit the stale reference after interface shutdown to     cause a denial of service or possibly execute code in     kernel mode.

  - CVE-2005-2800     Jan Blunck discovered that repeated failed reads of     /proc/scsi/sg/devices leak memory, which allows a denial     of service attack.

  - CVE-2005-2973     Tetsuo Handa discovered that the udp_v6_get_port()     function from the IPv6 code can be forced into an     endless loop, which allows a denial of service attack.

  - CVE-2005-3044     Vasiliy Averin discovered that the reference counters     from sockfd_put() and fput() can be forced into     overlapping, which allows a denial of service attack     through a NULL pointer dereference.

  - CVE-2005-3053     Eric Dumazet discovered that the set_mempolicy() system     call accepts a negative value for its first argument,     which triggers a BUG() assert. This allows a denial of     service attack.

  - CVE-2005-3055     Harald Welte discovered that if a process issues a USB     Request Block (URB) to a device and terminates before     the URB completes, a stale pointer would be     dereferenced. This could be used to trigger a denial of     service attack.

  - CVE-2005-3180     Pavel Roskin discovered that the driver for Orinoco     wireless cards clears its buffers insufficiently. This     could leak sensitive information into user space.

  - CVE-2005-3181     Robert Derr discovered that the audit subsystem uses an     incorrect function to free memory, which allows a denial     of service attack.

  - CVE-2005-3257     Rudolf Polzer discovered that the kernel improperly     restricts access to the KDSKBSENT ioctl, which can     possibly lead to privilege escalation.

  - CVE-2005-3356     Doug Chapman discovered that the mq_open syscall can be     tricked into decrementing an internal counter twice,     which allows a denial of service attack through a kernel     panic.

  - CVE-2005-3358     Doug Chapman discovered that passing a zero bitmask to     the set_mempolicy() system call leads to a kernel panic,     which allows a denial of service attack.

  - CVE-2005-3783     The ptrace code using CLONE_THREAD didn't use the thread     group ID to determine whether the caller is attaching to     itself, which allows a denial of service attack.

  - CVE-2005-3784     The auto-reaping of child processes functionality     included ptraced-attached processes, which allows denial     of service through dangling references.

  - CVE-2005-3806     Yen Zheng discovered that the IPv6 flow label code     modified an incorrect variable, which could lead to     memory corruption and denial of service.

  - CVE-2005-3847     It was discovered that a threaded real-time process,     which is currently dumping core can be forced into a     dead-lock situation by sending it a SIGKILL signal,     which allows a denial of service attack. 

  - CVE-2005-3848     Ollie Wild discovered a memory leak in the     icmp_push_reply() function, which allows denial of     service through memory consumption.

  - CVE-2005-3857     Chris Wright discovered that excessive allocation of     broken file lock leases in the VFS layer can exhaust     memory and fill up the system logging, which allows     denial of service.

  - CVE-2005-3858     Patrick McHardy discovered a memory leak in the     ip6_input_finish() function from the IPv6 code, which     allows denial of service.

  - CVE-2005-4605     Karl Janmar discovered that a signedness error in the     procfs code can be exploited to read kernel memory,     which may disclose sensitive information.

  - CVE-2005-4618     Yi Ying discovered that sysctl does not properly enforce     the size of a buffer, which allows a denial of service     attack.

  - CVE-2006-0095     Stefan Rompf discovered that dm_crypt does not clear an     internal struct before freeing it, which might disclose     sensitive information.

  - CVE-2006-0096     It was discovered that the SDLA driver's capability     checks were too lax for firmware upgrades.

  - CVE-2006-0482     Ludovic Courtes discovered that get_compat_timespec()     performs insufficient input sanitizing, which allows a     local denial of service attack.

  - CVE-2006-1066     It was discovered that ptrace() on the ia64 architecture     allows a local denial of service attack, when preemption     is enabled.

Rudolf Polzer reported an abuse of the 'loadkeys' command. By redefining one or more keys and tricking another user (like root) into logging in on a text console and typing something that involves the redefined keys, a local user could cause execution of arbitrary commands with the privileges of the target user. The updated kernel restricts the usage of 'loadkeys' to root. (CVE-2005-3257)

The ptrace() system call did not correctly check whether a process tried to attach to itself. A local attacker could exploit this to cause a kernel crash. (CVE-2005-3783)

A Denial of Service vulnerability was found in the handler that automatically cleans up and terminates child processes that are not correctly handled by their parent process ('auto-reaper'). The check did not correctly handle processes which were currently traced by another process. A local attacker could exploit this to cause a kernel crash. (CVE-2005-3784)

A locking problem was discovered in the POSIX timer cleanup handling on process exit. A local attacker could exploit this to cause the machine to hang (Denial of Service). This flaw only affects multiprocessor (SMP) systems. (CVE-2005-3805)

A Denial of Service vulnerability was discovered in the IPv6 flowlabel handling code. By invoking setsockopt(IPV6_FLOWLABEL_MGR) in a special way, a local attacker could cause memory corruption which eventually led to a kernel crash. (CVE-2005-3806)

A memory leak was discovered in the VFS lease handling. These operations are commonly executed by the Samba server, which led to steady memory exhaustion. By repeatedly triggering the affected operations in quick succession, a local attacker could exploit this to drain all memory, which leads to a Denial of Service. (CVE-2005-3807)

An integer overflow was discovered in the invalidate_inode_pages2_range() function. By issuing 64-bit mmap calls on a 32 bit system, a local user could exploit this to crash the machine, thereby causing Denial of Service. This flaw does not affect the amd64 platform, and does only affect Ubuntu 5.10. (CVE-2005-3808)

Ollie Wild discovered a memory leak in the icmp_push_reply() function.
By sending a large amount of specially crafted packets, a remote attacker could exploit this to drain all memory, which eventually leads to a Denial of Service. (CVE-2005-3848)

Chris Wrigth found a Denial of Service vulnerability in the time_out_leases() function. By allocating a large number of VFS file lock leases and having them timeout at the same time, a large number of 'printk' debugging statements was generated at the same time, which could exhaust kernel memory. (CVE-2005-3857)

Patrick McHardy discovered a memory leak in the ip6_input_finish() function. A remote attacker could exploit this by sending specially crafted IPv6 packets, which would eventually drain all available kernel memory, thus causing a Denial of Service. (CVE-2005-3858).

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.

Multiple vulnerabilities in the Linux 2.6 kernel have been discovered and corrected in this update :

A stack-based buffer overflow in the sendmsg function call in versions prior to 2.6.13.1 allow local users to execute arbitrary code by calling sendmsg and modifying the message contents in another thread (CVE-2005-2490).

The raw_sendmsg function in versions prior to 2.6.13.1 allow local users to cause a DoS (change hardware state) or read from arbitrary memory via crafted input (CVE-2005-2492).

The ipt_recent module in versions prior to 2.6.12 does not properly perform certain tests when the jiffies value is greater than LONG_MAX, which can cause ipt_recent netfilter rules to block too early (CVE-2005-2873).

Multiple vulnerabilities in versions prior to 2.6.13.2 allow local users to cause a DoS (oops from null dereference) via fput in a 32bit ioctl on 64-bit x86 systems or sockfd_put in the 32-bit routing_ioctl function on 64-bit systems (CVE-2005-3044).

Versions 2.6.8 to 2.6.14-rc2 allow local users to cause a DoS (oops) via a userspace process that issues a USB Request Block (URB) to a USB device and terminates before the URB is finished, which leads to a stale pointer reference (CVE-2005-3055).

drm.c in version 2.6.13 and earlier creates a debug file in sysfs with world-readable and world-writable permissions, allowing local users to enable DRM debugging and obtain sensitive information (CVE-2005-3179).

The Orinoco driver in 2.6.13 and earlier does not properly clear memory from a previously used packet whose length is increased, allowing remote attackers to obtain sensitive information (CVE-2005-3180).

Kernels 2.6.13 and earlier, when CONFIG_AUDITSYSCALL is enabled, use an incorrect function to free names_cache memory, preventing the memory from being tracked by AUDITSYSCALL code and leading to a memory leak (CVE-2005-3181).

The VT implementation in version 2.6.12 allows local users to use certain IOCTLs on terminals of other users and gain privileges (CVE-2005-3257).

A race condition in ip_vs_conn_flush in versions prior to 2.6.13, when running on SMP systems, allows local users to cause a DoS (null dereference) by causing a connection timer to expire while the connection table is being flushed before the appropriate lock is acquired (CVE-2005-3274).

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

Multiple vulnerabilities in the Linux 2.6 kernel have been discovered and corrected in this update :

An integer overflow in vc_resize (CVE-2004-1333).

A race condition in the sysfs_read_file and sysfs_write_file functions in 2.6.10 and earlier allows local users to read kernel memory and cause a DoS (crash) via large offsets in sysfs files (CVE-2004-2302).

An integer signedness error in scsi_ioctl.c (CVE-2005-0180).

Netfilter allows a local user to cause a DoS (memory consumption) via certain packet fragments that are reassembled twice, which causes a data structure to be allocated twice (CVE-2005-0210).

A DoS in pkt_ioctl in pktcdvc.c (CVE-2005-1589).

An array index overflow in the xfrm_sk_policy_insert function in xfrm_user.c allows local users to cause a DoS (oops or deadlock) and possibly execute arbitrary code (CVE-2005-2456).

The zisofs driver in versions prior to 2.6.12.5 allows local users and remove attackers to cause a DoS (crash) via a crafted compressed ISO filesystem (CVE-2005-2457).

inflate.c in the zlib routines in versions prior to 2.6.12.5 allow remove attackers to cause a DoS (crash) via a compressed file with 'improper tables' (CVE-2005-2458).

The huft_build function in inflate.c in the zlib routines in versions prior to 2.6.12.5 returns the wrong value, allowing remote attackers to cause a DoS (crash) via a certain compressed file that leads to a NULL pointer dereference (CVE-2005-2459).

A stack-based buffer overflow in the sendmsg function call in versions prior to 2.6.13.1 allow local users to execute arbitrary code by calling sendmsg and modifying the message contents in another thread (CVE-2005-2490).

vlan_dev.c in version 2.6.8 allows remote attackers to cause a DoS (oops from null dereference) via certain UDP packets that lead to a function call with the wrong argument (CVE-2005-2548).

The kernel does not properly restrict socket policy access to users with the CAP_NET_ADMIN capability, which could allow local users to conduct unauthorized activities via ipv4/ip_sockglue.c and ipv6/ipv6_sockglue.c (CVE-2005-2555).

A memory leak in the seq_file implementation in the SCSI procfs interface (sg.c) in 2.6.13 and earlier allows a local user to cause a DoS (memory consumption) via certain repeated reads from /proc/scsi/gs/devices file which is not properly handled when the next() interator returns NULL or an error (CVE-2005-2800).

xattr.c in the ext2 and ext3 file system code does not properly compare the name_index fields when sharing xattr blocks which could prevent ACLs from being applied (CVE-2005-2801).

The ipt_recent module in versions prior to 2.6.12 when running on 64bit processors allows remote attackers to cause a DoS (kernel panic) via certain attacks such as SSH brute force (CVE-2005-2872).

The ipt_recent module in versions prior to 2.6.12 does not properly perform certain tests when the jiffies value is greater than LONG_MAX, which can cause ipt_recent netfilter rules to block too early (CVE-2005-2873).

Multiple vulnerabilities in versions prior to 2.6.13.2 allow local users to cause a DoS (oops from null dereference) via fput in a 32bit ioctl on 64-bit x86 systems or sockfd_put in the 32-bit routing_ioctl function on 64-bit systems (CVE-2005-3044).

The sys_set_mempolicy function in mempolicy.c allows local users to cause a DoS via a negative first argument (CVE-2005-3053).

Versions 2.6.8 to 2.6.14-rc2 allow local users to cause a DoS (oops) via a userspace process that issues a USB Request Block (URB) to a USB device and terminates before the URB is finished, which leads to a stale pointer reference (CVE-2005-3055).

The Orinoco driver in 2.6.13 and earlier does not properly clear memory from a previously used packet whose length is increased, allowing remote attackers to obtain sensitive information (CVE-2005-3180).

Kernels 2.6.13 and earlier, when CONFIG_AUDITSYSCALL is enabled, use an incorrect function to free names_cache memory, preventing the memory from being tracked by AUDITSYSCALL code and leading to a memory leak (CVE-2005-3181).

The VT implementation in version 2.6.12 allows local users to use certain IOCTLs on terminals of other users and gain privileges (CVE-2005-3257).

Exec does not properly clear posix-timers in multi-threaded environments, which result in a resource leak and could allow a large number of multiple local users to cause a DoS by using more posix- timers than specified by the quota for a single user (CVE-2005-3271).

The rose_rt_ioctl function rose_route.c in versions prior to 2.6.12 does not properly verify the ndigis argument for a new route, allowing an attacker to trigger array out-of-bounds errors with a large number of digipeats (CVE-2005-3273).

A race condition in ip_vs_conn_flush in versions prior to 2.6.13, when running on SMP systems, allows local users to cause a DoS (null dereference) by causing a connection timer to expire while the connection table is being flushed before the appropriate lock is acquired (CVE-2005-3274).

The NAT code in versions prior to 2.6.13 incorrectly declares a variable to be static, allowing remote attackers to cause a DoS (memory corruption) by causing two packets for the same protocol to be NATed at the same time (CVE-2005-3275).

The sys_get_thread_area function in process.c in versions prior to 2.6.12.4 and 2.6.13 does not clear a data structure before copying it to userspace, which may allow a user process to obtain sensitive information (CVE-2005-3276).

The following non-security fixes are also applied :

Driver updates were made to the aic97xx and sata_sil modules.

Support was added for ATI ipx400 chipsets, for IDE and sound.

A build problem with icecream on the x86_64 platform was fixed.

The pin1 APIC timer on RS480-based motherboards was disabled.

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
22560	Debian DSA-1018-2 : kernel-source-2.4.27 - several vulnerabilities	Nessus	Debian Local Security Checks	high
22559	Debian DSA-1017-1 : kernel-source-2.6.8 - several vulnerabilities	Nessus	Debian Local Security Checks	critical
20775	Ubuntu 4.10 / 5.04 / 5.10 : linux-source-2.6.8.1/-2.6.10/-2.6.12 vulnerabilities (USN-231-1)	Nessus	Ubuntu Local Security Checks	high
20466	Mandrake Linux Security Advisory : kernel (MDKSA-2005:235)	Nessus	Mandriva Local Security Checks	medium
20450	Mandrake Linux Security Advisory : kernel (MDKSA-2005:219)	Nessus	Mandriva Local Security Checks	high

Detections

Analytics

CVE-2005-3257

high

Tenable Plugins

high

critical

high

medium

high