Gentoo Linux Security Advisory 201701-31 - Flex might generate code with a buffer overflow making applications using such scanners vulnerable to the execution of arbitrary code. Versions less than 2.6.1 are affected.
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Gentoo Linux Security Advisory GLSA 201701-31
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https://security.gentoo.org/
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Severity: Normal
Title: flex: Potential insecure code generation
Date: January 11, 2017
Bugs: #589820
ID: 201701-31
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Synopsis
========
Flex might generate code with a buffer overflow making applications
using such scanners vulnerable to the execution of arbitrary code.
Background
==========
flex is a programming tool used to generate scanners (programs which
recognize lexical patterns in text).
Affected packages
=================
-------------------------------------------------------------------
Package / Vulnerable / Unaffected
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1 sys-devel/flex < 2.6.1 >= 2.6.1
Description
===========
A heap-based buffer overflow in the yy_get_next_buffer function in Flex
might allow context-dependent attackers to cause a denial of service or
possibly execute arbitrary code via vectors involving num_to_read.
Impact
======
Context-dependent attackers could cause a Denial of Service condition
or possibly execute arbitrary code with the privileges of the process.
Workaround
==========
There is no known workaround at this time.
Resolution
==========
All flex users should upgrade to the latest version:
# emerge --sync
# emerge --ask --oneshot --verbose ">=sys-devel/flex-2.6.1"
Packages which depend on flex may need to be recompiled. Tools such as
qdepends (included in app-portage/portage-utils) may assist in
identifying these packages:
# emerge -1 -a -v $(qdepends -CQ sys-devel/flex | sed 's/^/=/')
References
==========
[ 1 ] CVE-2016-6354
http://nvd.nist.gov/nvd.cfm?cvename=CVE-2016-6354
Availability
============
This GLSA and any updates to it are available for viewing at
the Gentoo Security Website:
https://security.gentoo.org/glsa/201701-31
Concerns?
=========
Security is a primary focus of Gentoo Linux and ensuring the
confidentiality and security of our users' machines is of utmost
importance to us. Any security concerns should be addressed to
security@gentoo.org or alternatively, you may file a bug at
https://bugs.gentoo.org.
License
=======
Copyright 2017 Gentoo Foundation, Inc; referenced text
belongs to its owner(s).
The contents of this document are licensed under the
Creative Commons - Attribution / Share Alike license.
http://creativecommons.org/licenses/by-sa/2.5