CVE-2013-6412: Medium severity Augeas augeas vulnerability
Augeas upstream commit 051c73a9:
https://github.com/hercules-team/augeas/commit/051c73a9
introduced a flaw in the way Augeas sets permissions on newly created files. The above commit aims to address a regression introduced in the fix for CVE-2012-0786 (see bug 772257 comment 39), which introduced a use of mkstemp() to create new files. mkstemp() always sets 0600 file permissions regardless of the current umask setting. Commit 051c73a9 attempts to fix file permissions based on umask setting, but it does not correctly handle certain umask values, causing Augeas to make newly created files world writable. A local user could possibly use this flaw to modify configuration files created by an application using Augeas.
Other sources
The transformsave function in transform.c in Augeas 1.0.0 through 1.1.0 does not properly calculate the permission values when the umask contains a "7," which causes world-writable permissions to be used for new files and allows local users to modify the files via unspecified vectors.
— MITRE
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
augeasto a version that resolves this vulnerability.Fixed in 1.1.0Patch 051c73a9 - Configuration
Ensure transform_save in transform.c correctly calculates permission values when the umask contains a "7"; otherwise newly created files may become world-writable and allow local users to modify configuration files created by an application using Augeas.
augeas (transform_save in transform.c) umask contains "7" = handle correctly to avoid world-writable permissions - Compensating control
While remediating, restrict local-user access to any configuration files that applications modify via Augeas to prevent unauthorized modification in the presence of world-writable files.
Event History
Frequently Asked Questions
What is the severity of CVE-2013-6412?
CVE-2013-6412 is considered a medium severity vulnerability due to its potential impact on file permission settings in Augeas.
How do I fix CVE-2013-6412?
To fix CVE-2013-6412, upgrade Augeas to version 1.1.1 or later where the issue has been addressed.
What software is affected by CVE-2013-6412?
CVE-2013-6412 affects Augeas versions 1.0.0 and 1.1.0.
What type of vulnerability is CVE-2013-6412?
CVE-2013-6412 is a permissions vulnerability affecting the file creation process in Augeas.
Is CVE-2013-6412 exploitable?
CVE-2013-6412 can be exploited to create files with incorrect permissions, potentially leading to unauthorized access.