CVE-2017-3265: Medium severity Oracle MySQL vulnerability
Multiple cases of insecure use of chmod and chown were found in the MySQL init script:
- In database directory initialization code: https://github.com/mysql/mysql-server/blob/mysql-5.6.34/packaging/rpm-oel/mysql.init#L97
- In code handling error log file creation and permission setting: https://github.com/mysql/mysql-server/blob/mysql-5.6.34/packaging/rpm-oel/mysql.init#L73
The mysql OS user could use these flaws to escalate privileges to root.
Note that the second issue is only exploitable in configurations where log file is stored in a directory writable to the mysql OS user. If log file is stored in the /var/log directory, mysql user is not able to replace it with a link to some other file.
This issue was fixed in MySQL versions 5.5.54, 5.6.35, and 5.7.17. The following related entry can be found in the release notes:
Initialization scripts create the error log file only if the base directory is /var/log or /var/lib.
http://dev.mysql.com/doc/relnotes/mysql/5.5/en/news-5-5-54.html http://dev.mysql.com/doc/relnotes/mysql/5.6/en/news-5-6-35.html http://dev.mysql.com/doc/relnotes/mysql/5.7/en/news-5-7-17.html
MySQL upstream commit:
https://github.com/mysql/mysql-server/commit/53230ba274a37fa13d65e802c6ef3766cd0c6d91#diff-5fccc3d0e109e8f9ad0653728bd1d975
Other sources
Vulnerability in the MySQL Server component of Oracle MySQL (subcomponent: Server: Packaging). Supported versions that are affected are 5.5.53 and earlier, 5.6.34 and earlier and 5.7.16 and earlier. Difficult to exploit vulnerability allows high privileged attacker with logon to the infrastructure where MySQL Server executes to compromise MySQL Server. Successful attacks require human interaction from a person other than the attacker. Successful attacks of this vulnerability can result in unauthorized access to critical data or complete access to all MySQL Server accessible data and unauthorized ability to cause a hang or frequently repeatable crash (complete DOS) of MySQL Server. CVSS v3.0 Base Score 5.6 (Confidentiality and Availability impacts).
— MITRE
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
mysql-server (Oracle MySQL)to a version that resolves this vulnerability.Fixed in 5.5.54 - Upgrade
Upgrade
mysql-server (Oracle MySQL)to a version that resolves this vulnerability.Fixed in 5.6.35 - Upgrade
Upgrade
mysql-server (Oracle MySQL)to a version that resolves this vulnerability.Fixed in 5.7.17 - Compensating control
If the MySQL error log file is stored under /var/log or /var/lib, ensure the directory is not writable by the mysql OS user so the mysql user cannot replace the error log file with a link to another file.
Event History
Frequently Asked Questions
What is the severity of CVE-2017-3265?
CVE-2017-3265 has been classified as a difficult-to-exploit vulnerability with potentially significant impact if exploited.
How do I fix CVE-2017-3265?
To resolve CVE-2017-3265, update your MySQL Server to a version later than 5.5.53, 5.6.34, or 5.7.16.
Which MySQL versions are affected by CVE-2017-3265?
CVE-2017-3265 affects MySQL versions 5.5.53 and earlier, 5.6.34 and earlier, and 5.7.16 and earlier.
Who is primarily affected by CVE-2017-3265?
CVE-2017-3265 primarily affects environments where high-privileged attackers have logon access to the vulnerable MySQL Server.
Is CVE-2017-3265 specific to certain operating systems?
CVE-2017-3265 does not target specific operating systems but affects the MySQL Server component running on various platforms.