CVE-2010-0296: Input Validation
It was found that glibc's utility, responsible for editing of system's mtab table, improperly sanitized user supplied mount point names containing certain special character. Local attacker could use this flaw to add arbitrary mount points (corrupt system's "/etc/mtab" file) or, potentially, set unauthorized mount options. Other attacks are also possible.
Issue severity note: ------------------- The /etc/mtab file handles mounted devices and is automatically updated by the mount command (more precisely by the dedicated "mount" tool for relevant filesystem). Unprivileged user to be able to run such a tool (and modify content of /etc/mtab), this tool needs to be suid root enabled. The dedicated "mount" tools, as shipped with Red Hat Enterprise Linux (mount.cifs, mount.fuse, fusermount, mount.nfs, mount.nfs4) does NOT allow unprivileged user to use them (without prior grant of additional privileges from the privileged user) for editing of system's /etc/mtab file, which mitigates impact of this flaw.
Other sources
The encodename macro in misc/mntentr.c in the GNU C Library (aka glibc or libc6) 2.11.1 and earlier, as used by ncpmount and mount.cifs, does not properly handle newline characters in mountpoint names, which allows local users to cause a denial of service (mtab corruption), or possibly modify mount options and gain privileges, via a crafted mount request.
— Red Hat
Affected Software
Event History
Parent advisories
This vulnerability appears in the following advisories.
Frequently Asked Questions
What is the severity of CVE-2010-0296?
The severity of CVE-2010-0296 is classified as moderate due to its potential to cause denial of service.
How do I fix CVE-2010-0296?
To fix CVE-2010-0296, update the GNU C Library to version 2.11.2 or later.
What systems are affected by CVE-2010-0296?
CVE-2010-0296 affects various versions of the GNU C Library, specifically versions prior to 2.11.2.
What type of attack does CVE-2010-0296 enable?
CVE-2010-0296 enables local users to cause a denial of service through mtab corruption.
Can CVE-2010-0296 lead to any data modification?
Yes, CVE-2010-0296 may allow local users to modify mountpoint names under certain conditions.