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

critical Nessus Plugin ID 96425

Synopsis

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

Description

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.

Solution

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

https://security.gentoo.org/glsa/201701-31

Plugin Details

Severity: Critical

ID: 96425

File Name: gentoo_GLSA-201701-31.nasl

Version: 3.2

Type: local

Published: 1/12/2017

Updated: 1/11/2021

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 5.9

CVSS v2

Risk Factor: High

Base Score: 7.5

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

CVSS v3

Risk Factor: Critical

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

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

Patch Publication Date: 1/11/2017

Reference Information

CVE: CVE-2016-6354

GLSA: 201701-31