||expn in the am-utils and net-fs packages for Gentoo, rPath Linux, and other distributions, allows local users to overwrite arbitrary files via a symlink attack on the expn[PID] temporary file. NOTE: this is the same issue as CVE-2003-0308.1.
|Base: ||7.2 (as of 29-02-2008 - 15:04)|
An attacker positions a symbolic link in such a manner that the targeted user or application accesses the link's endpoint, assuming that it is accessing a file with the link's name. The endpoint file may be either output or input. If the file is output, the result is that the endpoint is modified, instead of a file at the intended location. Modifications to the endpoint file may include appending, overwriting, corrupting, changing permissions, or other modifications. In some variants of this attack the attacker may be able to control the change to a file while in other cases they cannot. The former is especially damaging since the attacker may be able to grant themselves increased privileges or insert false information, but the latter can also be damaging as it can expose sensitive information or corrupt or destroy vital system or application files. Alternatively, the endpoint file may serve as input to the targeted application. This can be used to feed malformed input into the target or to cause the target to process different information, possibly allowing the attacker to control the actions of the target or to cause the target to expose information to the attacker. Moreover, the actions taken on the endpoint file are undertaken with the permissions of the targeted user or application, which may exceed the permissions that the attacker would normally have.
Accessing, Modifying or Executing Executable Files
An attack of this type exploits a system's configuration that allows an attacker to either directly access an executable file, for example through shell access; or in a possible worst case allows an attacker to upload a file and then execute it. Web servers, ftp servers, and message oriented middleware systems which have many integration points are particularly vulnerable, because both the programmers and the administrators must be in synch regarding the interfaces and the correct privileges for each interface.
Leverage Executable Code in Non-Executable Files
An attack of this type exploits a system's trust in configuration and resource files, when the executable loads the resource (such as an image file or configuration file) the attacker has modified the file to either execute malicious code directly or manipulate the target process (e.g. application server) to execute based on the malicious configuration parameters. Since systems are increasingly interrelated mashing up resources from local and remote sources the possibility of this attack occurring is high.
The attack can also target server processes. The attacker edits the resource or configuration file, for example a web.xml file used to configure security permissions for a J2EE app server, adding role name "public" grants all users with the public role the ability to use the administration functionality.
The server trusts its configuration file to be correct, but when they are manipulated, the attacker gains full control.
Manipulating Input to File System Calls
An attacker manipulates inputs to the target software which the target software passes to file system calls in the OS. The goal is to gain access to, and perhaps modify, areas of the file system that the target software did not intend to be accessible.
|NASL family||Gentoo Local Security Checks |
|NASL id||GENTOO_GLSA-200804-09.NASL |
|description||The remote host is affected by the vulnerability described in GLSA-200804-09 (am-utils: Insecure temporary file creation)
Tavis Ormandy discovered that, when creating temporary files, the 'expn' utility does not check whether the file already exists.
A local attacker could exploit the vulnerability via a symlink attack to overwrite arbitrary files.
There is no known workaround at this time. |
|last seen||2019-02-21 |
|plugin id||31956 |
|title||GLSA-200804-09 : am-utils: Insecure temporary file creation |
|NASL family||Fedora Local Security Checks |
|NASL id||FEDORA_2008-10755.NASL |
|description||- Tue Dec 2 2008 Karel Zak 5:6.1.5-8.1
- fix #450754 - Amd does not work with 2.6.25 (thanks to Philippe Troin)
- fix #435420 - CVE-2008-1078 am-utils: insecure usage of temporary files
- fix autotools stuff
Note that Tenable Network Security has extracted the preceding description block directly from the Fedora 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||35385 |
|title||Fedora 9 : am-utils-6.1.5-8.1.fc9 (2008-10755) |
|contributor||Joshua Bressers |
|organization||Red Hat |
|statement||The risks associated with fixing this bug are greater than the low severity security risk.We therefore currently have no plans to fix this flaw in Red HatEnterprise Linux.
For more information please see the following bug:
|Last major update
||10-01-2009 - 00:00
||28-02-2008 - 21:44
||11-10-2018 - 16:29