PT-2019-5836 · Digium · Asterisk+1

Salah Ahmed · Published 2019-11-22 · Updated 2022-06-03 · CVE-2019-18976

Positive Technologies (AI Summary)

CVSS v2.0

7.8

High

Base vector

AV:N/AC:L/Au:N/C:N/I:N/A:C

Name of the Vulnerable Software and Affected Versions Asterisk versions prior to 13.21-x Certified Asterisk versions prior to 13.21-x

Description The issue is related to a null pointer dereference in the res pjsip t38.c component of Asterisk and Certified Asterisk systems. This can be exploited by a remote attacker to cause a denial of service. The vulnerability is triggered when the system receives a re-invite for T.38 faxing with a port of 0 and no c line in the SDP.

Recommendations For Asterisk versions prior to 13.21-x, update to version 13.21-x or later to resolve the issue. For Certified Asterisk versions prior to 13.21-x, update to version 13.21-x or later to resolve the issue. As a temporary workaround, consider restricting access to the res pjsip t38.c component until a patch is available.

Fix

NULL Pointer Dereference

Weakness Enumeration

CWE-476

Related Identifiers

BDU:2021-03298

CVE-2019-18976

DLA-2969-1

Affected Products

Asterisk

Certified Asterisk

References · 27

• https://cve.org/CVERecord?id=CVE-2019-18976 · Security Note
• https://asterisk.org/downloads/security-advisories · Vendor Advisory
• http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2019-18790 · Security Note
• https://security-tracker.debian.org/tracker/DLA-2969-1 · Vendor Advisory
• http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2019-18976 · Security Note
• https://security-tracker.debian.org/tracker/source-package/asterisk · Vendor Advisory
• http://downloads.asterisk.org/pub/security/AST-2019-008.html · Vendor Advisory
• http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-28242 · Security Note
• https://bdu.fstec.ru/vul/2021-03298 · Security Note
• http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2019-13161 · Security Note
• https://security-tracker.debian.org/tracker/CVE-2019-18976 · Vendor Advisory
• https://osv.dev/vulnerability/DLA-2969-1 · Vendor Advisory
• https://osv.dev/vulnerability/DEBIAN-CVE-2019-18976 · Vendor Advisory
• http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2019-18610 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2019-18976 · Security Note