#VU22936 Input validation error in Asterisk Open Source and Certified Asterisk - CVE-2019-18976
Published: November 22, 2019
Vulnerability identifier: #VU22936
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-2019-18976
CWE-ID: CWE-20
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerable software:
Asterisk Open Source
Certified Asterisk
Asterisk Open Source
Certified Asterisk
Software vendor:
Digium (Linux Support Services)
Digium (Linux Support Services)
Description
The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to insufficient validation of user-supplied input in the "res_pjsip_t38.c" module. A remote attacker can cause a denial of service condition when Asterisk receives a re-invite initiating T.38 faxing and has a port of 0 and no c line in the SDP.
Remediation
Install updates from vendor's website.