||nls_ascii.c in Linux before 18.104.22.168 uses an incorrect table size, which allows attackers to cause a denial of service (kernel crash) via a buffer overflow.
|Base: ||7.8 (as of 03-06-2005 - 13:58)|
Buffer Overflow via Environment Variables
This attack pattern involves causing a buffer overflow through manipulation of environment variables. Once the attacker finds that they can modify an environment variable, they may try to overflow associated buffers. This attack leverages implicit trust often placed in environment variables.
Buffer Overflow attacks target improper or missing bounds checking on buffer operations, typically triggered by input injected by an attacker. As a consequence, an attacker is able to write past the boundaries of allocated buffer regions in memory, causing a program crash or potentially redirection of execution as per the attackers' choice.
Client-side Injection-induced Buffer Overflow
This type of attack exploits a buffer overflow vulnerability in targeted client software through injection of malicious content from a custom-built hostile service.
Filter Failure through Buffer Overflow
In this attack, the idea is to cause an active filter to fail by causing an oversized transaction. An attacker may try to feed overly long input strings to the program in an attempt to overwhelm the filter (by causing a buffer overflow) and hoping that the filter does not fail securely (i.e. the user input is let into the system unfiltered).
An attacker exploits a weakness in the MIME conversion routine to cause a buffer overflow and gain control over the mail server machine. The MIME system is designed to allow various different information formats to be interpreted and sent via e-mail. Attack points exist when data are converted to MIME compatible format and back.
Overflow Binary Resource File
An attack of this type exploits a buffer overflow vulnerability in the handling of binary resources. Binary resources may include music files like MP3, image files like JPEG files, and any other binary file. These attacks may pass unnoticed to the client machine through normal usage of files, such as a browser loading a seemingly innocent JPEG file. This can allow the attacker access to the execution stack and execute arbitrary code in the target process. This attack pattern is a variant of standard buffer overflow attacks using an unexpected vector (binary files) to wrap its attack and open up a new attack vector. The attacker is required to either directly serve the binary content to the victim, or place it in a locale like a MP3 sharing application, for the victim to download. The attacker then is notified upon the download or otherwise locates the vulnerability opened up by the buffer overflow.
Buffer Overflow via Symbolic Links
This type of attack leverages the use of symbolic links to cause buffer overflows. An attacker can try to create or manipulate a symbolic link file such that its contents result in out of bounds data. When the target software processes the symbolic link file, it could potentially overflow internal buffers with insufficient bounds checking.
Overflow Variables and Tags
This type of attack leverages the use of tags or variables from a formatted configuration data to cause buffer overflow. The attacker crafts a malicious HTML page or configuration file that includes oversized strings, thus causing an overflow.
Buffer Overflow via Parameter Expansion
In this attack, the target software is given input that the attacker knows will be modified and expanded in size during processing. This attack relies on the target software failing to anticipate that the expanded data may exceed some internal limit, thereby creating a buffer overflow.
Buffer Overflow in an API Call
This attack targets libraries or shared code modules which are vulnerable to buffer overflow attacks. An attacker who has access to an API may try to embed malicious code in the API function call and exploit a buffer overflow vulnerability in the function's implementation. All clients that make use of the code library thus become vulnerable by association. This has a very broad effect on security across a system, usually affecting more than one software process.
Buffer Overflow in Local Command-Line Utilities
This attack targets command-line utilities available in a number of shells. An attacker can leverage a vulnerability found in a command-line utility to escalate privilege to root.
|NASL family||Red Hat Local Security Checks |
|NASL id||REDHAT-RHSA-2005-092.NASL |
|description||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.
The Linux kernel handles the basic functions of the operating system.
This advisory includes fixes for several security issues :
iSEC Security Research discovered multiple vulnerabilities in the IGMP functionality. These flaws could allow a local user to cause a denial of service (crash) or potentially gain privileges. Where multicast applications are being used on a system, these flaws may also allow remote users to cause a denial of service. The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CVE-2004-1137 to this issue.
iSEC Security Research discovered a flaw in the page fault handler code that could lead to local users gaining elevated (root) privileges on multiprocessor machines. (CVE-2005-0001)
iSEC Security Research discovered a VMA handling flaw in the uselib(2) system call of the Linux kernel. A local user could make use of this flaw to gain elevated (root) privileges. (CVE-2004-1235)
A flaw affecting the OUTS instruction on the AMD64 and Intel EM64T architecture was discovered. A local user could use this flaw to write to privileged IO ports. (CVE-2005-0204)
The Direct Rendering Manager (DRM) driver in Linux kernel 2.6 does not properly check the DMA lock, which could allow remote attackers or local users to cause a denial of service (X Server crash) or possibly modify the video output. (CVE-2004-1056)
OGAWA Hirofumi discovered incorrect tables sizes being used in the filesystem Native Language Support ASCII translation table. This could lead to a denial of service (system crash). (CVE-2005-0177)
Michael Kerrisk discovered a flaw in the 2.6.9 kernel which allows users to unlock arbitrary shared memory segments. This flaw could lead to applications not behaving as expected. (CVE-2005-0176)
Improvements in the POSIX signal and tty standards compliance exposed a race condition. This flaw can be triggered accidentally by threaded applications or deliberately by a malicious user and can result in a denial of service (crash) or in occasional cases give access to a small random chunk of kernel memory. (CVE-2005-0178)
The PaX team discovered a flaw in mlockall introduced in the 2.6.9 kernel. An unprivileged user could use this flaw to cause a denial of service (CPU and memory consumption or crash). (CVE-2005-0179)
Brad Spengler discovered multiple flaws in sg_scsi_ioctl in the 2.6 kernel. An unprivileged user may be able to use this flaw to cause a denial of service (crash) or possibly other actions. (CVE-2005-0180)
Kirill Korotaev discovered a missing access check regression in the Red Hat Enterprise Linux 4 kernel 4GB/4GB split patch. On systems using the hugemem kernel, a local unprivileged user could use this flaw to cause a denial of service (crash). (CVE-2005-0090)
A flaw in the Red Hat Enterprise Linux 4 kernel 4GB/4GB split patch can allow syscalls to read and write arbitrary kernel memory. On systems using the hugemem kernel, a local unprivileged user could use this flaw to gain privileges. (CVE-2005-0091)
An additional flaw in the Red Hat Enterprise Linux 4 kernel 4GB/4GB split patch was discovered. On x86 systems using the hugemem kernel, a local unprivileged user may be able to use this flaw to cause a denial of service (crash). (CVE-2005-0092)
All 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. |
|last seen||2019-02-21 |
|plugin id||17183 |
|title||RHEL 4 : kernel (RHSA-2005:092) |
|NASL family||Ubuntu Local Security Checks |
|NASL id||UBUNTU_USN-82-1.NASL |
Michael Kerrisk noticed an insufficient permission checking in the shmctl() function. Any process was permitted to lock/unlock any System V shared memory segment that fell within the the RLIMIT_MEMLOCK limit (that is the maximum size of shared memory that unprivileged users can acquire). This allowed am unprivileged user process to unlock locked memory of other processes, thereby allowing them to be swapped out.
Usually locked shared memory is used to store passphrases and other sensitive content which must not be written to the swap space (where it could be read out even after a reboot).
OGAWA Hirofumi noticed that the table sizes in nls_ascii.c were incorrectly set to 128 instead of 256. This caused a buffer overflow in some cases which could be exploited to crash the kernel.
A race condition was found in the terminal handling of the 'setsid()' function, which is used to start new process sessions.
David Coulson noticed a design flaw in the netfilter/iptables module.
By sending specially crafted packets, a remote attacker could exploit this to crash the kernel or to bypass firewall rules.
Fixing this vulnerability required a change in the Application Binary Interface (ABI) of the kernel. This means that third-party user installed modules might not work any more with the new kernel, so this fixed kernel has a new ABI version number. You have to recompile and reinstall all third-party modules.
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. |
|last seen||2019-02-21 |
|plugin id||20706 |
|title||Ubuntu 4.10 : linux-source-22.214.171.124 vulnerabilities (USN-82-1) |
|name||Aharon Chernin |
|organization||SCAP.com, LLC |
|name||Dragos Prisaca |
|organization||G2, Inc. |
|comment||The operating system installed on the system is Red Hat Enterprise Linux 4 |
|comment||CentOS Linux 4.x |
|comment||Oracle Linux 4.x |
|description||nls_ascii.c in Linux before 126.96.36.199 uses an incorrect table size, which allows attackers to cause a denial of service (kernel crash) via a buffer overflow. |
|title||nls_ascii.c in Linux before 188.8.131.52 uses an incorrect table size, which allows attackers to cause a denial of service (kernel crash) via a buffer overflow. |
|Last major update
||17-10-2016 - 23:08
||07-03-2005 - 00:00
||10-10-2017 - 21:29