Integer overflow in the do_replace function in netfilter for Linux before 2.6.16-rc3, when using "virtualization solutions" such as OpenVZ, allows local users with CAP_NET_ADMIN rights to cause a buffer overflow in the copy_from_user function.

An integer overflow was discovered in the do_replace() function. A local user process with the CAP_NET_ADMIN capability could exploit this to execute arbitrary commands with full root privileges. However, none of Ubuntu's supported packages use this capability with any non-root user, so this only affects you if you use some third party software like the OpenVZ virtualization system. (CVE-2006-0038)

On EMT64 CPUs, the kernel did not properly handle uncanonical return addresses. A local user could exploit this to trigger a kernel crash.
(CVE-2006-0744)

Al Viro discovered a local Denial of Service in the sysfs write buffer handling. By writing a block with a length exactly equal to the processor's page size to any writable file in /sys, a local attacker could cause a kernel crash. (CVE-2006-1055)

Jan Beulich discovered an information leak in the handling of registers for the numeric coprocessor when running on AMD processors.
This allowed processes to see the coprocessor execution state of other processes, which could reveal sensitive data in the case of cryptographic computations. (CVE-2006-1056)

Marcel Holtmann discovered that the sys_add_key() did not check that a new user key is added to a proper keyring. By attempting to add a key to a normal user key (which is not a keyring), a local attacker could exploit this to crash the kernel. (CVE-2006-1522)

Ingo Molnar discovered that the SCTP protocol connection tracking module in netfilter got stuck in an infinite loop on certain empty packet chunks. A remote attacker could exploit this to cause the computer to hang. (CVE-2006-1527)

The SCSI I/O driver did not correctly handle the VM_IO flag for memory mapped pages used for data transfer. A local user could exploit this to cause a kernel crash. (CVE-2006-1528)

The choose_new_parent() contained obsolete debugging code. A local user could exploit this to cause a kernel crash. (CVE-2006-1855)

Kostik Belousov discovered that the readv() and writev() functions did not query LSM modules for access permission. This could be exploited to circumvent access restrictions defined by LSM modules such as SELinux or AppArmor. (CVE-2006-1856)

The SCTP driver did not properly verify certain parameters when receiving a HB-ACK chunk. By sending a specially crafted packet to an SCTP socket, a remote attacker could exploit this to trigger a buffer overflow, which could lead to a crash or possibly even arbitrary code execution. (CVE-2006-1857)

The sctp_walk_params() function in the SCTP driver incorrectly used rounded values for bounds checking instead of the precise values. By sending a specially crafted packet to an SCTP socket, a remote attacker could exploit this to crash the kernel. (CVE-2006-1858)

Bjoern Steinbrink reported a memory leak in the __setlease() function.
A local attacker could exploit this to exhaust kernel memory and render the computer unusable (Denial of Service). (CVE-2006-1859)

Daniel Hokka Zakrisson discovered that the lease_init() did not properly handle locking. A local attacker could exploit this to cause a kernel deadlock (Denial of Service). (CVE-2006-1860)

Mark Moseley discovered that the CIFS file system driver did not filter out '..\\' path components. A local attacker could exploit this to break out of a chroot environment on a mounted SMB share.
(CVE-2006-1863) The same vulnerability applies to the older smb file system. (CVE-2006-1864)

Hugh Dickins discovered that the mprotect() function allowed an user to change a read-only shared memory attachment to become writable, which bypasses IPC (inter-process communication) permissions.
(CVE-2006-2071)

The SCTP (Stream Control Transmission Protocol) driver triggered a kernel panic on unexpected packets while the session was in the CLOSED state, instead of silently ignoring the packets. A remote attacker could exploit this to crash the computer. (CVE-2006-2271)

The SCTP driver did not handle control chunks if they arrived in fragmented packets. By sending specially crafted packets to an SCTP socket, a remote attacker could exploit this to crash the target machine. (CVE-2006-2272)

The SCTP driver did not correctly handle packets containing more than one DATA fragment. By sending specially crafted packets to an SCTP socket, a remote attacker could exploit this to crash the target machine. (CVE-2006-2274)

The SCTP driver did not correcly buffer incoming packets. By sending a large number of small messages to a receiver application that cannot process the messages quickly enough, a remote attacker could exploit this to cause a deadlock in the target machine (Denial of Service).
(CVE-2006-2275)

Patrick McHardy discovered that the snmp_trap_decode() function did not correctly handle memory allocation in some error conditions. By sending specially crafted packets to a machine which uses the SNMP network address translation (NAT), a remote attacker could exploit this to crash that machine. (CVE-2006-2444)

In addition, the Ubuntu 6.06 LTS update fixes a range of bugs.

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.

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-2005-3359     Franz Filz discovered that some socket calls permit     causing inconsistent reference counts on loadable     modules, which allows local users to cause a denial of     service.

  - CVE-2006-0038     'Solar Designer' discovered that arithmetic computations     in netfilter's do_replace() function can lead to a     buffer overflow and the execution of arbitrary code.
    However, the operation requires CAP_NET_ADMIN     privileges, which is only an issue in virtualization     systems or fine grained access control systems.

  - CVE-2006-0039     'Solar Designer' discovered a race condition in     netfilter's do_add_counters() function, which allows     information disclosure of kernel memory by exploiting a     race condition. Likewise, it requires CAP_NET_ADMIN     privileges. 

  - CVE-2006-0456     David Howells discovered that the s390 assembly version     of the strnlen_user() function incorrectly returns some     string size values.

  - CVE-2006-0554     It was discovered that the ftruncate() function of XFS     can expose unallocated blocks, which allows information     disclosure of previously deleted files.

  - CVE-2006-0555     It was discovered that some NFS file operations on     handles mounted with O_DIRECT can force the kernel into     a crash.

  - CVE-2006-0557     It was discovered that the code to configure memory     policies allows tricking the kernel into a crash, thus     allowing denial of service.

  - CVE-2006-0558     It was discovered by Cliff Wickman that perfmon for the     IA64 architecture allows users to trigger a BUG()     assert, which allows denial of service.

  - CVE-2006-0741     Intel EM64T systems were discovered to be susceptible to     a local DoS due to an endless recursive fault related to     a bad ELF entry address.

  - CVE-2006-0742     Alan and Gareth discovered that the ia64 platform had an     incorrectly declared die_if_kernel() function as 'does     never return' which could be exploited by a local     attacker resulting in a kernel crash.

  - CVE-2006-0744     The Linux kernel did not properly handle uncanonical     return addresses on Intel EM64T CPUs, reporting     exceptions in the SYSRET instead of the next     instruction, causing the kernel exception handler to run     on the user stack with the wrong GS. This may result in     a DoS due to a local user changing the frames.

  - CVE-2006-1056     AMD64 machines (and other 7th and 8th generation     AuthenticAMD processors) were found to be vulnerable to     sensitive information leakage, due to how they handle     saving and restoring the FOP, FIP, and FDP x87 registers     in FXSAVE/FXRSTOR when an exception is pending. This     allows a process to determine portions of the state of     floating point instructions of other processes.

  - CVE-2006-1242     Marco Ivaldi discovered that there was an unintended     information disclosure allowing remote attackers to     bypass protections against Idle Scans (nmap -sI) by     abusing the ID field of IP packets and bypassing the     zero IP ID in DF packet countermeasure. This was a     result of the ip_push_pending_frames function improperly     incremented the IP ID field when sending a RST after     receiving unsolicited TCP SYN-ACK packets.

  - CVE-2006-1368     Shaun Tancheff discovered a buffer overflow (boundary     condition error) in the USB Gadget RNDIS implementation     allowing remote attackers to cause a DoS. While creating     a reply message, the driver allocated memory for the     reply data, but not for the reply structure. The kernel     fails to properly bounds-check user-supplied data before     copying it to an insufficiently sized memory buffer.
    Attackers could crash the system, or possibly execute     arbitrary machine code.

  - CVE-2006-1523     Oleg Nesterov reported an unsafe BUG_ON call in signal.c     which was introduced by RCU signal handling. The BUG_ON     code is protected by siglock while the code in     switch_exit_pids() uses tasklist_lock. It may be     possible for local users to exploit this to initiate a     denial of service attack (DoS).

  - CVE-2006-1524     Hugh Dickins discovered an issue in the madvise_remove()     function wherein file and mmap restrictions are not     followed, allowing local users to bypass IPC permissions     and replace portions of readonly tmpfs files with     zeroes.

  - CVE-2006-1525     Alexandra Kossovsky reported a NULL pointer dereference     condition in ip_route_input() that can be triggered by a     local user by requesting a route for a multicast IP     address, resulting in a denial of service (panic).

  - CVE-2006-1857     Vlad Yasevich reported a data validation issue in the     SCTP subsystem that may allow a remote user to overflow     a buffer using a badly formatted HB-ACK chunk, resulting     in a denial of service.

  - CVE-2006-1858     Vlad Yasevich reported a bug in the bounds checking code     in the SCTP subsystem that may allow a remote attacker     to trigger a denial of service attack when rounded     parameter lengths are used to calculate parameter     lengths instead of the actual values.

  - CVE-2006-1863     Mark Mosely discovered that chroots residing on an CIFS     share can be escaped with specially crafted 'cd'     sequences.

  - CVE-2006-1864     Mark Mosely discovered that chroots residing on an SMB     share can be escaped with specially crafted 'cd'     sequences.

  - CVE-2006-2271     The 'Mu security team' discovered that carefully crafted     ECNE chunks can cause a kernel crash by accessing     incorrect state stable entries in the SCTP networking     subsystem, which allows denial of service.

  - CVE-2006-2272     The 'Mu security team' discovered that fragmented SCTP     control chunks can trigger kernel panics, which allows     for denial of service attacks.

  - CVE-2006-2274     It was discovered that SCTP packets with two initial     bundled data packets can lead to infinite recursion,     which allows for denial of service attacks.

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-2006-0038     'Solar Designer' discovered that arithmetic computations     in netfilter's do_replace() function can lead to a     buffer overflow and the execution of arbitrary code.
    However, the operation requires CAP_NET_ADMIN     privileges, which is only an issue in virtualization     systems or fine grained access control systems.

  - CVE-2006-0039     'Solar Designer' discovered a race condition in     netfilter's do_add_counters() function, which allows     information disclosure of kernel memory by exploiting a     race condition. Like CVE-2006-0038, it requires     CAP_NET_ADMIN privileges.

  - CVE-2006-0741     Intel EM64T systems were discovered to be susceptible to     a local DoS due to an endless recursive fault related to     a bad ELF entry address.

  - CVE-2006-0742     Incorrectly declared die_if_kernel() function as 'does     never return' which could be exploited by a local     attacker resulting in a kernel crash.

  - CVE-2006-1056     AMD64 machines (and other 7th and 8th generation     AuthenticAMD processors) were found to be vulnerable to     sensitive information leakage, due to how they handle     saving and restoring the FOP, FIP, and FDP x87 registers     in FXSAVE/FXRSTOR when an exception is pending. This     allows a process to determine portions of the state of     floating point instructions of other processes.

  - CVE-2006-1242     Marco Ivaldi discovered that there was an unintended     information disclosure allowing remote attackers to     bypass protections against Idle Scans (nmap -sI) by     abusing the ID field of IP packets and bypassing the     zero IP ID in DF packet countermeasure. This was a     result of the ip_push_pending_frames function improperly     incremented the IP ID field when sending a RST after     receiving unsolicited TCP SYN-ACK packets.

  - CVE-2006-1343     Pavel Kankovsky reported the existence of a potential     information leak resulting from the failure to     initialize sin.sin_zero in the IPv4 socket code.

  - CVE-2006-1368     Shaun Tancheff discovered a buffer overflow (boundary     condition error) in the USB Gadget RNDIS implementation     allowing remote attackers to cause a DoS. While creating     a reply message, the driver allocated memory for the     reply data, but not for the reply structure. The kernel     fails to properly bounds-check user-supplied data before     copying it to an insufficiently sized memory buffer.
    Attackers could crash the system, or possibly execute     arbitrary machine code.

  - CVE-2006-1524     Hugh Dickins discovered an issue in the madvise_remove()     function wherein file and mmap restrictions are not     followed, allowing local users to bypass IPC permissions     and replace portions of readonly tmpfs files with     zeroes.

  - CVE-2006-1525     Alexandra Kossovsky reported a NULL pointer dereference     condition in ip_route_input() that can be triggered by a     local user by requesting a route for a multicast IP     address, resulting in a denial of service (panic).

  - CVE-2006-1857     Vlad Yasevich reported a data validation issue in the     SCTP subsystem that may allow a remote user to overflow     a buffer using a badly formatted HB-ACK chunk, resulting     in a denial of service.

  - CVE-2006-1858     Vlad Yasevich reported a bug in the bounds checking code     in the SCTP subsystem that may allow a remote attacker     to trigger a denial of service attack when rounded     parameter lengths are used to calculate parameter     lengths instead of the actual values.

  - CVE-2006-1864     Mark Mosely discovered that chroots residing on an SMB     share can be escaped with specially crafted 'cd'     sequences.

  - CVE-2006-2271     The 'Mu security team' discovered that carefully crafted     ECNE chunks can cause a kernel crash by accessing     incorrect state stable entries in the SCTP networking     subsystem, which allows denial of service.

  - CVE-2006-2272     The 'Mu security team' discovered that fragmented SCTP     control chunks can trigger kernel panics, which allows     for denial of service attacks.

  - CVE-2006-2274     It was discovered that SCTP packets with two initial     bundled data packets can lead to infinite recursion,     which allows for denial of service attacks.

Updated kernel packages are now available as part of ongoing support and maintenance of Red Hat Enterprise Linux version 4.

This update 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 fourth regular update to Red Hat Enterprise Linux 4.

New features introduced in this update include :

* Device Mapper mirroring support

* IDE diskdump support

* x86, AMD64 and Intel EM64T: Multi-core scheduler support enhancements

* Itanium: perfmon support for Montecito

* much improved support for IBM x460

* AMD PowerNow! patches to support Opteron Rev G

* Vmalloc support > 64MB

The following device drivers have been upgraded to new versions :

ipmi: 33.11 to 33.13 ib_mthca: 0.06 to 0.08 bnx2: 1.4.30 to 1.4.38 bonding: 2.6.1 to 2.6.3 e100: 3.4.8-k2-NAPI to 3.5.10-k2-NAPI e1000:
6.1.16-k3-NAPI to 7.0.33-k2-NAPI sky2: 0.13 to 1.1 tg3: 3.43-rh to 3.52-rh ipw2100: 1.1.0 to git-1.1.4 ipw2200: 1.0.0 to git-1.0.10 3w-9xxx: 2.26.02.001 to 2.26.04.010 ips: 7.10.18 to 7.12.02 iscsi_sfnet: 4:0.1.11-2 to 4:0.1.11-3 lpfc: 0:8.0.16.18 to 0:8.0.16.27 megaraid_sas: 00.00.02.00 to 00.00.02.03-RH1 qla2xxx: 8.01.02-d4 to 8.01.04-d7 qla6312: 8.01.02-d4 to 8.01.04-d7 sata_promise: 1.03 to 1.04 sata_vsc: 1.1 to 1.2 ibmvscsic: 1.5.5 to 1.5.6 ipr: 2.0.11.1 to 2.0.11.2

Added drivers :

dcdbas: 5.6.0-2 sata_mv: 0.6 sata_qstor: 0.05 sata_uli: 0.5 skge: 1.1 stex: 2.9.0.13 pdc_adma: 0.03

This update includes fixes for the security issues :

* a flaw in the USB devio handling of device removal that allowed a local user to cause a denial of service (crash) (CVE-2005-3055, moderate)

* a flaw in the ACL handling of nfsd that allowed a remote user to bypass ACLs for readonly mounted NFS file systems (CVE-2005-3623, moderate)

* a flaw in the netfilter handling that allowed a local user with CAP_NET_ADMIN rights to cause a buffer overflow (CVE-2006-0038, low)

* a flaw in the IBM S/390 and IBM zSeries strnlen_user() function that allowed a local user to cause a denial of service (crash) or to retrieve random kernel data (CVE-2006-0456, important)

* a flaw in the keyctl functions that allowed a local user to cause a denial of service (crash) or to read sensitive kernel memory (CVE-2006-0457, important)

* a flaw in unaligned accesses handling on Itanium processors that allowed a local user to cause a denial of service (crash) (CVE-2006-0742, important)

* a flaw in SELinux ptrace logic that allowed a local user with ptrace permissions to change the tracer SID to a SID of another process (CVE-2006-1052, moderate)

* an info leak on AMD-based x86 and x86_64 systems that allowed a local user to retrieve the floating point exception state of a process run by a different user (CVE-2006-1056, important)

* a flaw in IPv4 packet output handling that allowed a remote user to bypass the zero IP ID countermeasure on systems with a disabled firewall (CVE-2006-1242, low)

* a minor info leak in socket option handling in the network code (CVE-2006-1343, low)

* a flaw in the HB-ACK chunk handling of SCTP that allowed a remote user to cause a denial of service (crash) (CVE-2006-1857, moderate)

* a flaw in the SCTP implementation that allowed a remote user to cause a denial of service (deadlock) (CVE-2006-2275, moderate)

* a flaw in the socket buffer handling that allowed a remote user to cause a denial of service (panic) (CVE-2006-2446, important)

* a flaw in the signal handling access checking on PowerPC that allowed a local user to cause a denial of service (crash) or read arbitrary kernel memory on 64-bit systems (CVE-2006-2448, important)

* a flaw in the netfilter SCTP module when receiving a chunkless packet that allowed a remote user to cause a denial of service (crash) (CVE-2006-2934, important)

There were several 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 4.

The remote CentOS system is missing a security update which has been documented in Red Hat advisory RHSA-2006-0575.

ID	Name	Product	Family	Severity
27877	Ubuntu 5.04 / 5.10 / 6.06 LTS : linux-source-2.6.10/2.6.12/2.6.15 vulnerabilities (USN-302-1)	Nessus	Ubuntu Local Security Checks	high
22645	Debian DSA-1103-1 : kernel-source-2.6.8 - several vulnerabilities	Nessus	Debian Local Security Checks	critical
22639	Debian DSA-1097-1 : kernel-source-2.4.27 - several vulnerabilities	Nessus	Debian Local Security Checks	critical
22276	CentOS 4 : kernel (CESA-2006:0575)	Nessus	CentOS Local Security Checks	high
22221	RHEL 4 : kernel (RHSA-2006:0575)	Nessus	Red Hat Local Security Checks	high
801420	CentOS RHSA-2006-0575 Security Check	Log Correlation Engine	Generic	high

Detections

Analytics

CVE-2006-0038

critical

Tenable Plugins

high

critical

critical

high

high

high