Exim MBX symlink
|exim-mbx-symlink (59042)||Medium Risk|
Exim could allow a local attacker to launch a symlink attack, caused by a race condition related to MBX locking. If MBX locking is used, a local attacker could exploit this vulnerability by creating a symbolic link from a temporary file to various files on the system, which could allow the attacker to take ownership of another user's files on the system with elevated privileges.
Upgrade to the latest version of Exim (4.72 RC2 or later), available from the Exim Web site. See References.
- Exim Bugzilla Bug 989: CVE-2010-2024 - MBX locking race condition.
- Exim Web site: exim Internet Mailer.
- BID-40454: Exim MBX Locking Insecure Temporary File Creation Vulnerability
- CVE-2010-2024: transports/appendfile.c in Exim before 4.72, when MBX locking is enabled, allows local users to change permissions of arbitrary files or create arbitrary files, and cause a denial of service or possibly gain privileges, via a symlink attack on a lockfile in /tmp/.
- OSVDB ID: 65159: Exim transports/appendfile.c MBX Locking Race Condition Permission Modification
- SA40019: exim Hardlink Handling and MBX Locking Two Weaknesses
- Cambridge University Exim 4.66
May 26, 2010
The information within this database may change without notice. Use of this information constitutes acceptance for use in an AS IS condition. There are NO warranties, implied or otherwise, with regard to this information or its use. Any use of this information is at the user's risk. In no event shall the author/distributor (IBM Internet Security Systems X-Force) be held liable for any damages whatsoever arising out of or in connection with the use or spread of this information.
For corrections or additions please email ignore thisxforceignore this@ignore thisus.ignore thisibm.comignore this
* According to the Forum of Incident Response and Security Teams (FIRST), the Common Vulnerability Scoring System (CVSS) is an "industry open standard designed to convey vulnerability severity and help to determine urgency and priority of response." IBM PROVIDES THE CVSS SCORES "AS IS" WITHOUT WARRANTY OF ANY KIND, INCLUDING THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. CUSTOMERS ARE RESPONSIBLE FOR ASSESSING THE IMPACT OF ANY ACTUAL OR POTENTIAL SECURITY VULNERABILITY.
The information within this database may change without notice. Use of this information constitutes acceptance for use in an AS IS condition. There are NO warranties, implied or otherwise, with regard to this information or its use. Any use of this information is at the user's risk. In no event shall IBM be held liable for any damages whatsoever arising out of or in connection with the use or spread of this information.