High severity · published Nov 22, 2019
CVE-2019-18976
An issue was discovered in res_pjsip_t38.c in Sangoma Asterisk through 13.x and Certified Asterisk through 13.21-x
7.5
CVSS
12.8%
EPSS
No
On KEV
Description
An issue was discovered in res_pjsip_t38.c in Sangoma Asterisk through 13.x and Certified Asterisk through 13.21-x. If it receives a re-invite initiating T.38 faxing and has a port of 0 and no c line in the SDP, a NULL pointer dereference and crash will occur. This is different from CVE-2019-18940.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)12.8% · higher than 96% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AS
Asterisk · Digium
13.0.0 through 13.29.1 · source: NVD
CA
Certified Asterisk · Digium
13.21; 13.21; 13.21; 13.21; 13.21 · source: NVD
DL
Debian Linux · Debian
9.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2019-18976
CVE.org
https://www.cve.org/CVERecord?id=CVE-2019-18976
Vendor Advisory
http://downloads.asterisk.org/pub/security/AST-2019-008.html
Mailing List
https://lists.debian.org/debian-lts-announce/2022/04/msg00001.html
Third Party Advisory
https://packetstormsecurity.com/files/155436/Asterisk-Project-Security-Advisory-AST-2019-008.html
Mailing List
https://seclists.org/fulldisclosure/2019/Nov/20
Vendor Advisory
https://www.asterisk.org/downloads/security-advisories
Third Party Advisory
https://www.cybersecurity-help.cz/vdb/SB2019112218?affChecked=1
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