Secunia Research: Common Unix Printing System "cupsdProcessIPPRequest()" Denial of Service Vulnerability

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                     Secunia Research 2018/10/11

        Common Unix Printing System "cupsdProcessIPPRequest()"
                   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

* CUPS version 2.2.8. Other versions may also be affected.

* macOS High Sierra version 10.13.5.

* macOS Sierra version 10.12.6.

* OS X El Capitan version 10.11.6.

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2) Severity

Rating: Less critical
Impact: Denial of Service
Where:  Local Area Network

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3) Description of Vulnerability

Secunia Research has discovered a vulnerability in Common Unix
Printing System, which can be exploited by malicious people to cause
a DoS (Denial of Service).

An   error   within   the   "cupsdProcessIPPRequest()"   function 
(scheduler/ipp.c) when handling print job attributes can be exploited
to trigger a NULL pointer dereference by sending a specially crafted
IPP request.

The vulnerability is confirmed in CUPS version 2.2.8.
Other versions may also be affected.

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4) Solution

CUPS fixed in the source code repository.
https://github.com/apple/cups/commit/918d2b07482d9a5a3728cc11cf94b44832b0b215

For Apple products update to a fixed version or apply Security Update.
https://support.apple.com/en-us/HT208937

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5) Time Table

2018/06/13 - Vendor contacted with vulnerability details.
2018/06/14 - Vendor acknowledged to receive the report.
2018/06/15 - Vendor status update.
2018/08/02 - Vendor contacted for status update.
2018/08/03 - Vendor status update.
2018/08/20 - Release of vendor patch.
2018/08/30 - Release of Secunia Advisory SA83448.
2018/09/25 - Apple security advisory updated.
2018/10/03 - Update of Secunia Advisories SA83448 and SA84013.
2018/10/11 - Public disclosure of Secunia Research Advisory.

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6) Credits
 
Jakub Jirasek, Secunia Research at Flexera.

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7) References

The Apple CNA has assigned CVE-2018-4276 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/2018-22/

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