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                     Secunia Research 2018/02/28

   Linux Kernel "_sctp_make_chunk()" Denial of Service Vulnerability

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Table of Contents

Affected Software....................................................1
Severity.............................................................2
Description of Vulnerability.........................................3
Solution.............................................................4
Time Table...........................................................5
Credits..............................................................6
References...........................................................7
About Flexera .......................................................8
Verification.........................................................9

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1) Affected Software

* Linux Kernel version 4.15.0.
  Other versions may also by affected.

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2) Severity

Rating: Not critical
Impact: Denial of Service
Where:  Local System

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3) Description of Vulnerability

Secunia Research has discovered a vulnerability in Linux Kernel, which
can be exploited by malicious, local users to cause a DoS (Denial of
Service).

An   error   in   the   "_sctp_make_chunk()"   function
(net/sctp/sm_make_chunk.c) when handling SCTP packets length can be
exploited to cause a kernel crash.

The vulnerability is confirmed in versions 4.15.0-r7 and 4.15.0.
Other versions may also be affected.

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4) Solution

Fixed in the source code repository.
https://git.kernel.org/linus/07f2c7ab6f8d0a7e7c5764c4e6cc9c52951b9d9c

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5) Time Table

2018/02/07 - Linux Kernel team contacted with vulnerability details.
2018/02/07 - Linux Kernel team advised reporting the vulnerability
             publicly via netdev mailing list.
2018/02/07 - Public disclosure of the vulnerability on netdev mailing
             list.
2018/02/09 - The vulnerability additionally reported on linux-sctp
             mailing list.
2018/02/28 - Release of Secunia Advisory SA81331.
2018/02/28 - Public disclosure of Secunia Research Advisory.

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6) Credits

Jakub Jirasek, Secunia Research at Flexera.

Additionally reported by Alexey Kodanev.

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7) References

The Flexera CNA has assigned CVE-2018-5803 identifier for the
vulnerability through the Common Vulnerabilities and Exposures (CVE)
project.

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8) About Flexera

Flexera helps application producers and enterprises increase
application usage and the value they derive from their software.

http://www.flexera.com

Flexera delivers market-leading Software Vulnerability Management
solutions enabling enterprises to proactively identify and
remediate software vulnerabilities, effectively reducing the risk of
costly security breaches.

https://www.flexera.com/enterprise/products/

Flexera supports and contributes to the community in several
ways. We have always believed that reliable vulnerability
intelligence and tools to aid identifying and fixing vulnerabilities
should be freely available for consumers to ensure that users,
who care about their online privacy and security, can stay secure.
Only a few vendors address vulnerabilities in a proper way and help
users get updated and stay secure. End-users (whether private
individuals or businesses) are otherwise left largely alone, and
that is why back in 2002, Secunia Research started investigating,
coordinating disclosure and verifying software vulnerabilities.
In 2016, Secunia Research became a part of Flexera and today
our in-house software vulnerability research remains the core of
the Software Vulnerability Management products at Flexera.

https://www.flexera.com/enterprise/company/about/secunia-research/

The public Secunia Advisory database contains information for
researchers, security enthusiasts, and consumers to lookup individual
products and vulnerabilities and assess, whether they need to take
any actions to secure their systems or whether a given vulnerability
has already been discovered

https://secuniaresearch.flexerasoftware.com/community/advisories/

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9) Verification

Please verify this advisory by visiting the Secunia Research website:
https://secuniaresearch.flexerasoftware.com/secunia_research/2018-2

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