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AUSCERT External Security Bulletin Redistribution
ESB-2021.2516
AST-2021-007
23 July 2021
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AusCERT Security Bulletin Summary
---------------------------------
Product: Asterisk
Publisher: Asterisk
Operating System: Windows
UNIX variants (UNIX, Linux, OSX)
Impact/Access: Denial of Service -- Existing Account
Resolution: Patch/Upgrade
CVE Names: CVE-2021-31878
Original Bulletin:
http://downloads.asterisk.org/pub/security/AST-2021-007.html
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Asterisk Project Security Advisory - AST-2021-007
Product Asterisk
Summary Remote Crash Vulnerability in PJSIP channel driver
Nature of Advisory Denial of Service
Susceptibility Remote Authenticated Sessions
Severity Moderate
Exploits Known No
Reported On April 6, 2021
Reported By Ivan Poddubny
Posted On
Last Updated On July 6, 2021
Advisory Contact Jcolp AT sangoma DOT com
CVE Name CVE-2021-31878
Description When Asterisk receives a re-INVITE without SDP after having sent a BYE request
a crash will occur. This occurs due to the Asterisk channel no longer being
present while code assumes it is.
Modules Affected res_pjsip_session.c
Resolution Upgrade to one of the fixed versions of Asterisk or apply the appropriate
patch.
Affected Versions
Product Release
Series
Asterisk Open Source 16.x 16.17.0, 16.18.0, 16.19.0
Asterisk Open Source 18.x 18.3.0, 18.4.0, 18.5.0
Corrected In
Product Release
Asterisk Open Source 16.19.1, 18.5.1
Patches
Patch URL Revision
https://downloads.digium.com/pub/security/ Asterisk 16
AST-2021-007 -16.diff
https://downloads.digium.com/pub/security/ Asterisk 18
AST-2021-007 -18.diff
Links https://issues.asterisk.org/jira/browse/ASTERISK-29381
https://downloads.asterisk.org/pub/security/ AST-2021-007 .html
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This document may be superseded by later versions; if so, the latest version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 https://downloads.digium.com/pub/security/ AST-2021-007 .pdf
and https://downloads.digium.com/pub/security/ AST-2021-007 .html
Revision History
Date Editor Revisions Made
April 28, 2021 Joshua Colp Initial revision
Asterisk Project Security Advisory - AST-2021-007
Copyright (C) 2021 Digium, Inc. All Rights Reserved.
Permission is hereby granted to distribute and publish this advisory in its
original, unaltered form.
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