Article Number | 000036249 | ||||||||||||
Applies To |
| ||||||||||||
Article Summary | Resolution steps for capacity overflow attack vulnerability on /var file system. | ||||||||||||
Alert Impact | Impacted - Apply RSA Remedy | ||||||||||||
Alert Impact Explanation | The /var/tmp directory contains temporary files written by programs. There are several known capacity overflow attacks for the /var file system. | ||||||||||||
Resolution | A capacity overflow attack on the /var file system can be mitigated by binding the /var/tmp directory to the /tmp directory. This ensures no user or programs can consume all of the space in the /var file system. The following steps can be taken to automatically bind /var/tmp to /tmp at system boot time.
If the grep command returns no output, or returns only lines that do not "bind" /var/tmp, continue with step 3 below. If the grep command returns an error, or finds a line that "binds" /var/tmp, do not continue.
The cat command should show that the last line in /etc/fstab is now:
| ||||||||||||
Notes | Reboot RequiredA reboot is required to perform the mount because there are many lock files and communication-related temporary files maintained in /var/tmp. Running an explicit mount command in a running system may lead to issues when a local Oracle database is in use. BackoutShould this change need to be backed out, the original /etc/fstab file can be copied from the backup directory to its original location with the following command:
|
Read and use the information in this RSA Security Advisory to assist in avoiding any situation that might arise from the problems described herein. If you have any questions regarding this product alert, contact RSA Software Technical Support at 1- 800 995 5095. RSA Security LLC and its affiliates, including without limitation, its ultimate parent company, Dell EMC, distributes RSA Security Advisories in order to bring to the attention of users of the affected RSA products, important security information. RSA recommends that all users determine the applicability of this information to their individual situations and take appropriate action. The information set forth herein is provided 'as is' without warranty of any kind. RSA disclaims all warranties, either express or implied, including the warranties of merchantability, fitness for a particular purpose, title and non-infringement. In no event, shall RSA, its affiliates or suppliers, be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if RSA, its affiliates or suppliers have been advised of the possibility of such damages. Some jurisdictions do not allow the exclusion or limitation of liability for consequential or incidental damages, so the foregoing limitation may not apply.