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NIST has updated the NVD program announcement page with additional information regarding recent concerns and the temporary delays in enrichment efforts.

CVE-2023-49786 Detail


Asterisk is an open source private branch exchange and telephony toolkit. In Asterisk prior to versions 18.20.1, 20.5.1, and 21.0.1; as well as certified-asterisk prior to 18.9-cert6; Asterisk is susceptible to a DoS due to a race condition in the hello handshake phase of the DTLS protocol when handling DTLS-SRTP for media setup. This attack can be done continuously, thus denying new DTLS-SRTP encrypted calls during the attack. Abuse of this vulnerability may lead to a massive Denial of Service on vulnerable Asterisk servers for calls that rely on DTLS-SRTP. Commit d7d7764cb07c8a1872804321302ef93bf62cba05 contains a fix, which is part of versions 18.20.1, 20.5.1, 21.0.1, amd 18.9-cert6.


CVSS 3.x Severity and Metrics:

Base Score:  5.9 MEDIUM
Vector:  CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Nist CVSS score does not match with CNA score
CNA:  GitHub, Inc.
Base Score:  7.5 HIGH
Vector:  CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

NVD Analysts use publicly available information to associate vector strings and CVSS scores. We also display any CVSS information provided within the CVE List from the CNA.

Note: It is possible that the NVD CVSS may not match that of the CNA. The most common reason for this is that publicly available information does not provide sufficient detail or that information simply was not available at the time the CVSS vector string was assigned.

References to Advisories, Solutions, and Tools

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Hyperlink Resource
http://packetstormsecurity.com/files/176251/Asterisk-20.1.0-Denial-Of-Service.html Exploit  Third Party Advisory  VDB Entry 
http://seclists.org/fulldisclosure/2023/Dec/24 Exploit  Mailing List  Third Party Advisory 
http://www.openwall.com/lists/oss-security/2023/12/15/7 Exploit  Mailing List 
https://github.com/EnableSecurity/advisories/tree/master/ES2023-01-asterisk-dtls-hello-race Exploit 
https://github.com/asterisk/asterisk/commit/d7d7764cb07c8a1872804321302ef93bf62cba05 Patch 
https://github.com/asterisk/asterisk/security/advisories/GHSA-hxj9-xwr8-w8pq Exploit  Vendor Advisory 

Weakness Enumeration

CWE-ID CWE Name Source
CWE-362 Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition') cwe source acceptance level NIST  
CWE-703 Improper Check or Handling of Exceptional Conditions Provider acceptance level GitHub, Inc.  

Known Affected Software Configurations Switch to CPE 2.2

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Change History

6 change records found show changes

Quick Info

CVE Dictionary Entry:
NVD Published Date:
NVD Last Modified:
GitHub, Inc.