Netfilter in the Linux kernel 2.6.8.1 allows local users to cause a denial of service (memory consumption) via certain packet fragments that are reassembled twice, which causes a data structure to be allocated twice.

Updated kernel packages that fix several security issues are now available for Red Hat Enterprise Linux 4.

This update has been rated as having important security impact by the Red Hat Security Response Team.

[Updated 9 August 2005] The advisory text has been updated to show that this update fixed the security issue named CVE-2005-0210 but not CVE-2005-0209. The issue CVE-2005-0209 was actually fixed by RHSA-2005:420. No changes have been made to the packages associated with this advisory.

The Linux kernel handles the basic functions of the operating system.

A flaw in the fib_seq_start function was discovered. A local user could use this flaw to cause a denial of service (system crash) via /proc/net/route. (CVE-2005-1041)

A flaw in the tmpfs file system was discovered. A local user could use this flaw to cause a denial of service (system crash). (CVE-2005-0977)

An integer overflow flaw was found when writing to a sysfs file. A local user could use this flaw to overwrite kernel memory, causing a denial of service (system crash) or arbitrary code execution.
(CVE-2005-0867)

Keith Owens reported a flaw in the Itanium unw_unwind_to_user function. A local user could use this flaw to cause a denial of service (system crash) on Itanium architectures. (CVE-2005-0135)

A flaw in the NFS client O_DIRECT error case handling was discovered.
A local user could use this flaw to cause a denial of service (system crash). (CVE-2005-0207)

A small memory leak when defragmenting local packets was discovered that affected the Linux 2.6 kernel netfilter subsystem. A local user could send a large number of carefully crafted fragments leading to memory exhaustion (CVE-2005-0210)

A flaw was discovered in the Linux PPP driver. On systems allowing remote users to connect to a server using ppp, a remote client could cause a denial of service (system crash). (CVE-2005-0384)

A flaw was discovered in the ext2 file system code. When a new directory is created, the ext2 block written to disk is not initialized, which could lead to an information leak if a disk image is made available to unprivileged users. (CVE-2005-0400)

A flaw in fragment queuing was discovered that affected the Linux kernel netfilter subsystem. On systems configured to filter or process network packets (e.g. firewalling), a remote attacker could send a carefully crafted set of fragmented packets to a machine and cause a denial of service (system crash). In order to sucessfully exploit this flaw, the attacker would need to know or guess some aspects of the firewall ruleset on the target system. (CVE-2005-0449)

A number of flaws were found in the Linux 2.6 kernel. A local user could use these flaws to read kernel memory or cause a denial of service (crash). (CVE-2005-0529, CVE-2005-0530, CVE-2005-0531)

An integer overflow in sys_epoll_wait in eventpoll.c was discovered. A local user could use this flaw to overwrite low kernel memory. This memory is usually unused, not usually resulting in a security consequence. (CVE-2005-0736)

A flaw when freeing a pointer in load_elf_library was discovered. A local user could potentially use this flaw to cause a denial of service (crash). (CVE-2005-0749)

A flaw was discovered in the bluetooth driver system. On systems where the bluetooth modules are loaded, a local user could use this flaw to gain elevated (root) privileges. (CVE-2005-0750)

A race condition was discovered that affected the Radeon DRI driver. A local user who has DRI privileges on a Radeon graphics card may be able to use this flaw to gain root privileges. (CVE-2005-0767)

Multiple range checking flaws were discovered in the iso9660 file system handler. An attacker could create a malicious file system image which would cause a denial or service or potentially execute arbitrary code if mounted. (CVE-2005-0815)

A flaw was discovered when setting line discipline on a serial tty. A local user may be able to use this flaw to inject mouse movements or keystrokes when another user is logged in. (CVE-2005-0839)

Red Hat Enterprise Linux 4 users are advised to upgrade their kernels to the packages associated with their machine architectures and configurations as listed in this erratum.

Please note that

Updated kernel packages are now available as part of ongoing support and maintenance of Red Hat Enterprise Linux version 3. This is the sixth regular update.

This security advisory has been rated as having important security impact by the Red Hat Security Response Team.

The Linux kernel handles the basic functions of the operating system.

This is the sixth regular kernel update to Red Hat Enterprise Linux 3.

New features introduced by this update include :

  - diskdump support on HP Smart Array devices -     netconsole/netdump support over bonded interfaces - new     chipset and device support via PCI table updates -     support for new 'oom-kill' and 'kscand_work_percent'     sysctls - support for dual core processors and ACPI     Power Management timers on AMD64 and Intel EM64T systems

There were many bug fixes in various parts of the kernel. The ongoing effort to resolve these problems has resulted in a marked improvement in the reliability and scalability of Red Hat Enterprise Linux 3.

There were numerous driver updates and security fixes (elaborated below). Other key areas affected by fixes in this update include kswapd, inode handling, the SATA subsystem, diskdump handling, ptrace() syscall support, and signal handling.

The following device drivers have been upgraded to new versions :

3w-9xxx ---- 2.24.03.008RH cciss ------ 2.4.58.RH1 e100 ------- 3.4.8-k2 e1000 ------ 6.0.54-k2 emulex ----- 7.3.2 fusion ----- 2.06.16i.01 iscsi ------ 3.6.2.1 ipmi ------- 35.4 lpfcdfc ---- 1.2.1 qlogic ----- 7.05.00-RH1 tg3 -------- 3.27RH

The following security bugs were fixed in this update :

  - a flaw in syscall argument checking on Itanium systems     that allowed a local user to cause a denial of service     (crash) (CVE-2005-0136)

  - a flaw in stack expansion that allowed a local user of     mlockall() to cause a denial of service (memory     exhaustion) (CVE-2005-0179)

  - a small memory leak in network packet defragmenting that     allowed a remote user to cause a denial of service     (memory exhaustion) on systems using netfilter     (CVE-2005-0210)

  - flaws in ptrace() syscall handling on AMD64 and Intel     EM64T systems that allowed a local user to cause a     denial of service (crash) (CVE-2005-0756, CVE-2005-1762,     CVE-2005-2553)

  - flaws in ISO-9660 file system handling that allowed the     mounting of an invalid image on a CD-ROM to cause a     denial of service (crash) or potentially execute     arbitrary code (CVE-2005-0815)

  - a flaw in ptrace() syscall handling on Itanium systems     that allowed a local user to cause a denial of service     (crash) (CVE-2005-1761)

  - a flaw in the alternate stack switching on AMD64 and     Intel EM64T systems that allowed a local user to cause a     denial of service (crash) (CVE-2005-1767)

  - race conditions in the ia32-compat support for exec()     syscalls on AMD64, Intel EM64T, and Itanium systems that     could allow a local user to cause a denial of service     (crash) (CVE-2005-1768)

  - flaws in IPSEC network handling that allowed a local     user to cause a denial of service or potentially gain     privileges (CVE-2005-2456, CVE-2005-2555)

  - a flaw in sendmsg() syscall handling on 64-bit systems     that allowed a local user to cause a denial of service     or potentially gain privileges (CVE-2005-2490)

  - flaws in unsupported modules that allowed     denial-of-service attacks (crashes) or local privilege     escalations on systems using the drm, coda, or moxa     modules (CVE-2004-1056, CVE-2005-0124, CVE-2005-0504)

  - potential leaks of kernel data from jfs and ext2 file     system handling (CVE-2004-0181, CVE-2005-0400)

Note: The kernel-unsupported package contains various drivers and modules that are unsupported and therefore might contain security problems that have not been addressed.

All Red Hat Enterprise Linux 3 users are advised to upgrade their kernels to the packages associated with their machine architectures and configurations as listed in this erratum.

A remote Denial of Service vulnerability was discovered in the Netfilter IP packet handler. This allowed a remote attacker to crash the machine by sending specially crafted IP packet fragments.
(CAN-2005-0209)

The Netfilter code also contained a memory leak. Certain locally generated packet fragments are reassembled twice, which caused a double allocation of a data structure. This could be locally exploited to crash the machine due to kernel memory exhaustion. (CAN-2005-0210)

Ben Martel and Stephen Blackheath found a remote Denial of Service vulnerability in the PPP driver. This allowed a malicious pppd client to crash the server machine. (CAN-2005-0384)

Georgi Guninski discovered a buffer overflow in the ATM driver. The atm_get_addr() function does not validate its arguments sufficiently, which could allow a local attacker to overwrite large portions of kernel memory by supplying a negative length argument. This could eventually lead to arbitrary code execution. (CAN-2005-0531)

Georgi Guninski also discovered three other integer comparison problems in the TTY layer, in the /proc interface and the ReiserFS driver. However, the previous Ubuntu security update (kernel version 2.6.8.1-16.11) already contained a patch which checks the arguments to these functions at a higher level and thus prevents these flaws from being exploited. (CAN-2005-0529, CAN-2005-0530, CAN-2005-0532)

Georgi Guninski discovered an integer overflow in the sys_epoll_wait() function which allowed local users to overwrite the first few kB of physical memory. However, very few applications actually use this space (dosemu is a notable exception), but potentially this could lead to privilege escalation. (CAN-2005-0736)

Eric Anholt discovered a race condition in the Radeon DRI driver. In some cases this allowed a local user with DRI privileges on a Radeon card to execute arbitrary code with root privileges.

Finally this update fixes a regression in the NFS server driver which was introduced in the previous security update (kernel version 2.6.8.1-16.11). We apologize for the inconvenience.
(https://bugzilla.ubuntulinux.org/show_bug.cgi?id=6749)

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 :

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

The remote Redhat Enterprise Linux 4 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2005:366 advisory.

    The Linux kernel handles the basic functions of the operating system.

    A flaw in the fib_seq_start function was discovered. A local user could use     this flaw to cause a denial of service (system crash) via /proc/net/route.
    (CAN-2005-1041)

    A flaw in the tmpfs file system was discovered. A local user could use this     flaw to cause a denial of service (system crash). (CAN-2005-0977)

    An integer overflow flaw was found when writing to a sysfs file. A local     user could use this flaw to overwrite kernel memory, causing a denial of     service (system crash) or arbitrary code execution. (CAN-2005-0867)

    Keith Owens reported a flaw in the Itanium unw_unwind_to_user function. A     local user could use this flaw to cause a denial of service (system crash)     on Itanium architectures. (CAN-2005-0135)

    A flaw in the NFS client O_DIRECT error case handling was discovered. A     local user could use this flaw to cause a denial of service (system crash).
    (CAN-2005-0207)

    A small memory leak when defragmenting local packets was discovered that     affected the Linux 2.6 kernel netfilter subsystem.  A local user could send     a large number of carefully crafted fragments leading to memory exhaustion     (CAN-2005-0210)

    A flaw was discovered in the Linux PPP driver. On systems allowing remote     users to connect to a server using ppp, a remote client could cause a     denial of service (system crash). (CAN-2005-0384)

    A flaw was discovered in the ext2 file system code. When a new directory is     created, the ext2 block written to disk is not initialized, which could     lead to an information leak if a disk image is made available to     unprivileged users. (CAN-2005-0400)

    A flaw in fragment queuing was discovered that affected the Linux kernel     netfilter subsystem. On systems configured to filter or process network     packets (e.g. firewalling), a remote attacker could send a carefully     crafted set of fragmented packets to a machine and cause a denial of     service (system crash). In order to sucessfully exploit this flaw, the     attacker would need to know or guess some aspects of the firewall ruleset     on the target system. (CAN-2005-0449)

    A number of flaws were found in the Linux 2.6 kernel. A local user could     use these flaws to read kernel memory or cause a denial of service (crash).
    (CAN-2005-0529, CAN-2005-0530, CAN-2005-0531)

    An integer overflow in sys_epoll_wait in eventpoll.c was discovered. A     local user could use this flaw to overwrite low kernel memory. This memory     is usually unused, not usually resulting in a security consequence.
    (CAN-2005-0736)

    A flaw when freeing a pointer in load_elf_library was discovered. A local     user could potentially use this flaw to cause a denial of service (crash).
    (CAN-2005-0749)

    A flaw was discovered in the bluetooth driver system. On systems where the     bluetooth modules are loaded, a local user could use this flaw to gain     elevated (root) privileges. (CAN-2005-0750)

    A race condition was discovered that affected the Radeon DRI driver. A     local user who has DRI privileges on a Radeon graphics card may be able to     use this flaw to gain root privileges. (CAN-2005-0767)

    Multiple range checking flaws were discovered in the iso9660 file system     handler. An attacker could create a malicious file system image which would     cause a denial or service or potentially execute arbitrary code if mounted.
    (CAN-2005-0815)

    A flaw was discovered when setting line discipline on a serial tty. A local     user may be able to use this flaw to inject mouse movements or keystrokes     when another user is logged in. (CAN-2005-0839)

    Red Hat Enterprise Linux 4 users are advised to upgrade their kernels     to the packages associated with their machine architectures and     configurations as listed in this erratum.

    Please note that

Tenable has extracted the preceding description block directly from the Red Hat Enterprise Linux security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote host is missing the patch for the advisory SUSE-SA:2005:018 (kernel).


The Linux kernel is the core component of the Linux system.

Several vulnerabilities were reported in the last few weeks which are fixed by this update.

ID	Name	Product	Family	Severity
21928	CentOS 3 / 4 : kernel (CESA-2005:366)	Nessus	CentOS Local Security Checks	high
21849	CentOS 3 : kernel (CESA-2005:663)	Nessus	CentOS Local Security Checks	medium
20721	Ubuntu 4.10 : linux-source-2.6.8.1 vulnerabilities (USN-95-1)	Nessus	Ubuntu Local Security Checks	high
20450	Mandrake Linux Security Advisory : kernel (MDKSA-2005:219)	Nessus	Mandriva Local Security Checks	high
19832	RHEL 3 : kernel (RHSA-2005:663)	Nessus	Red Hat Local Security Checks	medium
18095	RHEL 4 : kernel (RHSA-2005:366)	Nessus	Red Hat Local Security Checks	high
17617	SUSE-SA:2005:018: kernel	Nessus	SuSE Local Security Checks	high

Detections

Analytics

CVE-2005-0210

medium

Tenable Plugins

high

medium

high

high

medium

high

high