#VU50966 Input validation error in Asterisk Open Source - CVE-2021-26717

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Main Vulnerability Database Vulnerabilities #VU50966

#VU50966 Input validation error in Asterisk Open Source - CVE-2021-26717

Published: February 18, 2021 / Updated: February 26, 2021


Vulnerability identifier: #VU50966
Vulnerability risk: Medium
CVSSv4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2021-26717
CWE-ID: CWE-20
Exploitation vector: Remote access
Exploit availability: No public exploit available
Vulnerable software:
Asterisk Open Source
Software vendor:
Digium (Linux Support Services)

Description

The vulnerability allows a remote non-authenticated attacker to perform a denial of service (DoS) attack.

An issue was discovered in Sangoma Asterisk 16.x before 16.16.1, 17.x before 17.9.2, and 18.x before 18.2.1 and Certified Asterisk before 16.8-cert6. When re-negotiating for T.38, if the initial remote response was delayed just enough, Asterisk would send both audio and T.38 in the SDP. If this happened, and the remote responded with a declined T.38 stream, then Asterisk would crash.


Remediation

Install update from vendor's website.

External links