RHEL 6 : kernel (RHSA-2016:1939)

This script is Copyright (C) 2016-2017 Tenable Network Security, Inc.


Synopsis :

The remote Red Hat host is missing one or more security updates.

Description :

An update for kernel is now available for Red Hat Enterprise Linux 6.6
Extended Update Support.

Red Hat Product Security has rated this update as having a security
impact of Important. A Common Vulnerability Scoring System (CVSS) base
score, which gives a detailed severity rating, is available for each
vulnerability from the CVE link(s) in the References section.

The kernel packages contain the Linux kernel, the core of any Linux
operating system.

Security Fix(es) :

* It was found that the RFC 5961 challenge ACK rate limiting as
implemented in the Linux kernel's networking subsystem allowed an
off-path attacker to leak certain information about a given connection
by creating congestion on the global challenge ACK rate limit counter
and then measuring the changes by probing packets. An off-path
attacker could use this flaw to either terminate TCP connection and/or
inject payload into non-secured TCP connection between two endpoints
on the network. (CVE-2016-5696, Important)

Red Hat would like to thank Yue Cao (Cyber Security Group of the CS
department of University of California in Riverside) for reporting
this issue.

Bug Fix(es) :

* Previously, the BUG_ON() signal appeared in the fs_clear_inode()
function where the nfs_have_writebacks() function reported a positive
value for nfs_inode->npages. As a consequence, a kernel panic
occurred. The provided patch performs a serialization by holding the
inode i_lock over the check of PagePrivate and locking the request,
which fixes this bug. (BZ#1365163)

See also :

https://www.redhat.com/security/data/cve/CVE-2016-5696.html
http://rhn.redhat.com/errata/RHSA-2016-1939.html

Solution :

Update the affected packages.

Risk factor :

Medium / CVSS Base Score : 5.8
(CVSS2#AV:N/AC:M/Au:N/C:N/I:P/A:P)
CVSS Temporal Score : 4.8
(CVSS2#E:F/RL:OF/RC:ND)
Public Exploit Available : true

Family: Red Hat Local Security Checks

Nessus Plugin ID: 93762 ()

Bugtraq ID:

CVE ID: CVE-2016-5696

Ready to Amp Up Your Nessus Experience?

Get Nessus Professional to scan unlimited IPs, run compliance checks & more

Buy Nessus Professional Now