Medium severity · published Nov 6, 2020
CVE-2020-28242
An issue was discovered in Asterisk Open Source 13.x before 13.37.1, 16.x before 16.14.1, 17.x before 17.8.1, and 18.x before 18.0.1 and Certified Asterisk before 16.8-cert5
6.5
CVSS
1.5%
EPSS
No
On KEV
Description
An issue was discovered in Asterisk Open Source 13.x before 13.37.1, 16.x before 16.14.1, 17.x before 17.8.1, and 18.x before 18.0.1 and Certified Asterisk before 16.8-cert5. If Asterisk is challenged on an outbound INVITE and the nonce is changed in each response, Asterisk will continually send INVITEs in a loop. This causes Asterisk to consume more and more memory since the transaction will never terminate (even if the call is hung up), ultimately leading to a restart or shutdown of Asterisk. Outbound authentication must be configured on the endpoint for this to occur.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.5% · higher than 74% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AS
Asterisk · Sangoma
13.0 before 13.37.1; 16.0 before 16.14.1; 17.0 before 17.8.1; 18.0 before 18.0.1 · source: NVD
CA
Certified Asterisk · Asterisk
through 16.8.0 · source: NVD
DL
Debian Linux · Debian
9.0 · source: NVD
FE
Fedora · Fedoraproject
33 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-28242
CVE.org
https://www.cve.org/CVERecord?id=CVE-2020-28242
Vendor Advisory
http://downloads.asterisk.org/pub/security/AST-2020-002.html
Mailing List
https://lists.debian.org/debian-lts-announce/2022/04/msg00001.html
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QUS54QTQCYKR36EIULYD544GXDA644HB/
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