The execve system call in Linux 2.4.x records the file descriptor of the executable process in the file table of the calling process, which allows local users to gain read access to restricted file descriptors.

The IA-64 maintainers fixed several security related bugs in the Linux kernel 2.4.17 used for the IA-64 architecture, mostly by backporting fixes from 2.4.18. The corrections are listed below with the identification from the Common Vulnerabilities and Exposures (CVE) project :

  - CAN-2003-0001 :
    Multiple ethernet network interface card (NIC) device     drivers do not pad frames with null bytes, which allows     remote attackers to obtain information from previous     packets or kernel memory by using malformed packets, as     demonstrated by Etherleak.

  - CAN-2003-0018 :

    Linux kernel 2.4.10 through 2.4.21-pre4 does not     properly handle the O_DIRECT feature, which allows local     attackers with write privileges to read portions of     previously deleted files, or cause file system     corruption.

  - CAN-2003-0127 :

    The kernel module loader in Linux kernel 2.2.x before     2.2.25, and 2.4.x before 2.4.21, allows local users to     gain root privileges by using ptrace to attach to a     child process which is spawned by the kernel.

  - CAN-2003-0461 :

    The virtual file /proc/tty/driver/serial in Linux 2.4.x     reveals the exact number of characters used in serial     links, which could allow local users to obtain     potentially sensitive information such as the length of     passwords.

  - CAN-2003-0462 :

    A race condition in the way env_start and env_end     pointers are initialized in the execve system call and     used in fs/proc/base.c on Linux 2.4 allows local users     to cause a denial of service (crash).

  - CAN-2003-0476 :

    The execve system call in Linux 2.4.x records the file     descriptor of the executable process in the file table     of the calling process, which allows local users to gain     read access to restricted file descriptors.

  - CAN-2003-0501 :

    The /proc filesystem in Linux allows local users to     obtain sensitive information by opening various entries     in /proc/self before executing a setuid program, which     causes the program to fail to change the ownership and     permissions of those entries.

  - CAN-2003-0550 :

    The STP protocol, as enabled in Linux 2.4.x, does not     provide sufficient security by design, which allows     attackers to modify the bridge topology.

  - CAN-2003-0551 :

    The STP protocol implementation in Linux 2.4.x does not     properly verify certain lengths, which could allow     attackers to cause a denial of service.

  - CAN-2003-0552 :

    Linux 2.4.x allows remote attackers to spoof the bridge     Forwarding table via forged packets whose source     addresses are the same as the target.

  - CAN-2003-0961 :

    An integer overflow in brk system call (do_brk function)     for Linux kernel 2.4.22 and earlier allows local users     to gain root privileges.

  - CAN-2003-0985 :

    The mremap system call (do_mremap) in Linux kernel 2.4     and 2.6 does not properly perform boundary checks, which     allows local users to cause a denial of service and     possibly gain privileges by causing a remapping of a     virtual memory area (VMA) to create a zero length VMA.

A number of vulnerabilities have been discovered in the Linux kernel.

  - CAN-2003-0461: /proc/tty/driver/serial in Linux 2.4.x     reveals the exact number of characters used in serial     links, which could allow local users to obtain     potentially sensitive information such as the length of     passwords. This bug has been fixed by restricting access     to /proc/tty/driver/serial.
  - CAN-2003-0462: A race condition in the way env_start and     env_end pointers are initialized in the execve system     call and used in fs/proc/base.c on Linux 2.4 allows     local users to cause a denial of service (crash).

  - CAN-2003-0476: The execve system call in Linux 2.4.x     records the file descriptor of the executable process in     the file table of the calling process, which allows     local users to gain read access to restricted file     descriptors.

  - CAN-2003-0501: The /proc filesystem in Linux allows     local users to obtain sensitive information by opening     various entries in /proc/self before executing a setuid     program, which causes the program to fail to change the     ownership and permissions of those entries.

  - CAN-2003-0550: The STP protocol, as enabled in Linux     2.4.x, does not provide sufficient security by design,     which allows attackers to modify the bridge topology.
    This bug has been fixed by disabling STP by default.

  - CAN-2003-0551: The STP protocol, as enabled in Linux     2.4.x, does not provide sufficient security by design,     which allows attackers to modify the bridge topology.

  - CAN-2003-0552: Linux 2.4.x allows remote attackers to     spoof the bridge forwarding table via forged packets     whose source addresses are the same as the target.

  - CAN-2003-0018: Linux kernel 2.4.10 through 2.4.21-pre4     does not properly handle the O_DIRECT feature, which     allows local attackers with write privileges to read     portions of previously deleted files, or cause file     system corruption. This bug has been fixed by disabling     O_DIRECT.

  - CAN-2003-0619: Integer signedness error in the decode_fh     function of nfs3xdr.c in Linux kernel before 2.4.21     allows remote attackers to cause a denial of service     (kernel panic) via a negative size value within XDR data     of an NFSv3 procedure call.

This advisory covers only the i386 and alpha architectures. Other architectures will be covered by separate advisories.

Multiple vulnerabilities were discovered and fixed in the Linux kernel.

  - CVE-2003-0001: Multiple ethernet network card drivers do     not pad frames with null bytes which allows remote     attackers to obtain information from previous packets or     kernel memory by using special malformed packets.

  - CVE-2003-0244: The route cache implementation in the 2.4     kernel and the Netfilter IP conntrack module allows     remote attackers to cause a Denial of Service (DoS) via     CPU consumption due to packets with forged source     addresses that cause a large number of hash table     collisions related to the PREROUTING chain.

  - CVE-2003-0246: The ioperm implementation in 2.4.20 and     earlier kernels does not properly restrict privileges,     which allows local users to gain read or write access to     certain I/O ports.

  - CVE-2003-0247: A vulnerability in the TTY layer of the     2.4 kernel allows attackers to cause a kernel oops     resulting in a DoS.

  - CVE-2003-0248: The mxcsr code in the 2.4 kernel allows     attackers to modify CPU state registers via a malformed     address.

  - CVE-2003-0462: A file read race existed in the execve()     system call.

Kernels for 9.1/x86 are also available (see MDKSA-2003:066).

MandrakeSoft encourages all users to upgrade to these new kernels.

For full instructions on how to properly upgrade your kernel, please review http://www.mandrakesecure.net/en/docs/magic.php.

Updated kernel packages that address various security vulnerabilities, fix a number of bugs, and update various drivers are now available.

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

The execve system call in Linux 2.4.x records the file descriptor of the executable process in the file table of the calling process, which allows local users to gain read access to restricted file descriptors.
The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CVE-2003-0476 to this issue.

A number of bugfixes are included, including important fixes for the ext3 file system and timer code.

New features include limited support for non-cached NFS file sytems, Serial ATA (SATA) devices, and new alt-sysreq debugging options.

In addition, the following drivers have been updated :

  - e100 2.3.30-k1 - e1000 5.2.20-k1 - fusion 2.05.05+ - ips     6.10.52 - aic7xxx 6.2.36 - aic79xxx 1.3.10 - megaraid 2     2.00.9 - cciss 2.4.49

All users are advised to upgrade to these erratum packages, which contain backported patches addressing these issues.

Updated kernel packages that address various security vulnerabilities,
fix a number of bugs, and update various drivers are now available.

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

The execve system call in Linux 2.4.x records the file descriptor of
the executable process in the file table of the calling process, which
allows local users to gain read access to restricted file descriptors.
The Common Vulnerabilities and Exposures project (cve.mitre.org) has
assigned the name CVE-2003-0476 to this issue.

A number of bugfixes are included, including important fixes for the
ext3 file system and timer code.

New features include limited support for non-cached NFS file sytems,
Serial ATA (SATA) devices, and new alt-sysreq debugging options.

In addition, the following drivers have been updated :

  - e100 2.3.30-k1 - e1000 5.2.20-k1 - fusion 2.05.05+ - ips
    6.10.52 - aic7xxx 6.2.36 - aic79xxx 1.3.10 - megaraid 2
    2.00.9 - cciss 2.4.49

All users are advised to upgrade to these erratum packages, which
contain backported patches addressing these issues.

ID	Name	Product	Family	Severity
15260	Debian DSA-423-1 : linux-kernel-2.4.17-ia64 - several vulnerabilities	Nessus	Debian Local Security Checks	high
15195	Debian DSA-358-4 : linux-kernel-2.4.18 - several vulnerabilities	Nessus	Debian Local Security Checks	medium
14057	Mandrake Linux Security Advisory : kernel (MDKSA-2003:074)	Nessus	Mandriva Local Security Checks	critical
12442	RHEL 2.1 : kernel (RHSA-2003:408)	Nessus	Red Hat Local Security Checks	low
801584	Red Hat 2003-408 Security Check	Log Correlation Engine	Generic	high

Detections

Analytics

CVE-2003-0476

high

Tenable Plugins

high

medium

critical

low

high