ASA-2007-016: Remote crash vulnerability in Skinny channel driver

           Asterisk Project Security Advisory - ASA-2007-016

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| Product | Asterisk |
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| Summary | Remote crash vulnerability in Skinny channel |
| | driver |
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| Nature of Advisory | Denial of Service |
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| Susceptibility | Remote Unauthenticated Sessions |
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| Severity | Critical |
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| Exploits Known | No |
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| Reported On | July 13, 2007 |
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| Reported By | Will Drewry, Google Security Team |
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| Posted On | July 17, 2007 |
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| Last Updated On | July 17, 2007 |
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| Advisory Contact | Jason Parker <[email protected]> |
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| CVE Name | CVE-2007-3764 |
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| Description | The Asterisk Skinny channel driver, chan_skinny, has a |
| | remotely exploitable crash vulnerability. A segfault can |
| | occur when Asterisk receives a packet where the claimed |
| | length of the data is between 0 and 3, followed by |
| | length + 4 or more bytes, due to an overly large memcpy. |
| | The side effects of this extremely large memcpy have not |
| | been investigated. |
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| Resolution | All users that have chan_skinny enabled should upgrade to |
| | the appropriate version listed in the corrected in |
| | section of this advisory. As a workaround, users who do |
| | not require chan_skinny may add the line "noload => |
| | chan_skinny.so" (without quotes) to |
| | /etc/asterisk/modules.conf, and restart Asterisk. |
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| Links | |
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| Asterisk Project Security Advisories are posted at |
| http://www.asterisk.org/security. |
| |
| This document may be superseded by later versions; if so, the latest |
| version will be posted at |
| http://ftp.digium.com/pub/asa/ASA-2007-016.pdf. |
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           Asterisk Project Security Advisory - ASA-2007-016
          Copyright (c) 2007 Digium, Inc. All Rights Reserved.

Permission is hereby granted to distribute and publish this advisory in its
original, unaltered form.