Follow @Openwall on Twitter for new release announcements and other news
[<prev] [next>] [day] [month] [year] [list]
Date: Thu, 15 Aug 2019 13:37:57 +1000
From: Wade Mealing <wmealing@...hat.com>
To: oss-security@...ts.openwall.com
Subject: CVE-2019-10140 - linux kernel - system panic in overlayfs directory creation.

Red Hats kernel has a flaw in overlayfs which can cause a kernel panic and
possibly memory corruption.

An attacker with local access can create a denial of service situation via
NULL pointer dereference in ovl_posix_acl_create function in
fs/overlayfs/dir.c. The ovl_create function can return a positive number
leading to a null pointer derference of path in may_open. This can allow
attackers with ability to create directories on overlayfs to crash the
kernel creating a Denial Of Service (DOS) and possibly other memory
corruption.

The memory corruption claim may be a bit of a stretch, but it could be
possible that an attacker could pre-groom the memory where the null pointer
dereference exists, but I couldn't get this to work in practice, YMMV.

This flaw likely only affects Red Hat Enterprise Linux 7 based products as
this issue was created by by human-error in the back-porting process.  It
is very unlikely that non Red Hat Enterprise Linux derived distributions
contain this flaw.

Thanks,

Wade Mealing
Red Hat Product Security


Red Hat bugzilla:
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-10140

Proposed patch:
https://bugzilla.redhat.com/attachment.cgi?id=1535840

Powered by blists - more mailing lists

Please check out the Open Source Software Security Wiki, which is counterpart to this mailing list.

Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.