GLSA-201701-31 : flex: Potential insecure code generation

High Nessus Plugin ID 96425

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VPR Score: 5.9


The remote Gentoo host is missing one or more security-related patches.


The remote host is affected by the vulnerability described in GLSA-201701-31 (flex: Potential insecure code generation)

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.


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 --oneshot --ask --verbose $(qdepends -CQ sys-devel/flex | sed 's/^/=/')

See Also

Plugin Details

Severity: High

ID: 96425

File Name: gentoo_GLSA-201701-31.nasl

Version: 3.2

Type: local

Published: 2017/01/12

Updated: 2021/01/11

Dependencies: 12634

Risk Information

Risk Factor: High

VPR Score: 5.9

CVSS v2.0

Base Score: 7.5

Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P

CVSS v3.0

Base Score: 9.8

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Vulnerability Information

CPE: p-cpe:/a:gentoo:linux:flex, cpe:/o:gentoo:linux

Required KB Items: Host/local_checks_enabled, Host/Gentoo/release, Host/Gentoo/qpkg-list

Patch Publication Date: 2017/01/11

Reference Information

CVE: CVE-2016-6354

GLSA: 201701-31