CVE-2017-7533: Race Condition
A race condition was found in Linux kernel present since v3.14-rc1 upto v4.12 including. The race happens between threads of inotifyhandleevent() and vfsrename() while running the rename operation against the same file. As a result of the race the the next slab data or the slab's free list pointer can be corrupted with attacker-controlled data, which may lead to the privilege escalation.
The researchers of this flaw are Leilei Lin from Alibaba Group and Fan Wu and Shixiong Zhao from a research group supervised by Dr. Heming Cui of the Department of Computer Science, The University of Hong Kong. Thanks to Rui Gu and Prof.Junfeng Yang from Columbia University for tools and suggestions.
References:
http://seclists.org/oss-sec/2017/q3/240
https://access.redhat.com/security/vulnerabilities/3112931
https://patchwork.kernel.org/patch/9755753/
https://patchwork.kernel.org/patch/9755757/
https://www.mail-archive.com/linux-kernel@vger.kernel.org/msg1408967.html
https://bugzilla.kernel.org/showbug.cgi?id=196279 (restricted access)
Upstream patch: 49d31c2f389a
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=49d31c2f389acfe83417083e1208422b4091cd9
Other sources
Race condition in the fsnotify implementation in the Linux kernel through 4.12.4 allows local users to gain privileges or cause a denial of service (memory corruption) via a crafted application that leverages simultaneous execution of the inotifyhandleevent and vfsrename functions.
— Launchpad
Affected Software
Remediation
Patch Available
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Event History
Frequently Asked Questions
What is CVE-2017-7533?
CVE-2017-7533 is a vulnerability in the Linux kernel that allows local users to gain privileges or cause a denial of service through a crafted application.
How does CVE-2017-7533 work?
CVE-2017-7533 is caused by a race condition in the fsnotify implementation of the Linux kernel, which can be exploited by executing the inotify_handle_event and vfs_rename functions simultaneously.
What is the severity of CVE-2017-7533?
CVE-2017-7533 has a severity rating of high (7 out of 10).
Which software versions are affected by CVE-2017-7533?
CVE-2017-7533 affects various versions of the Linux kernel, including Ubuntu, Debian, and Google Android.
How can CVE-2017-7533 be fixed?
To fix CVE-2017-7533, it is recommended to update the affected software packages to the specified remedy versions or higher.