CVE-2020-28242
Publication date 6 November 2020
Last updated 26 August 2025
Ubuntu priority
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.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| asterisk | 25.10 questing |
Not affected
|
| 24.04 LTS noble |
Not affected
|
|
| 22.04 LTS jammy |
Not affected
|
|
| 20.04 LTS focal |
Vulnerable
|
|
| 18.04 LTS bionic |
Vulnerable
|
|
| 16.04 LTS xenial |
Vulnerable
|
|
| 14.04 LTS trusty | Not in release |
Patch details
| Package | Patch details |
|---|---|
| asterisk |
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score |
6.5 · Medium
|
| Attack vector | Network |
| Attack complexity | Low |
| Privileges required | Low |
| User interaction | None |
| Scope | Unchanged |
| Confidentiality | None |
| Integrity impact | None |
| Availability impact | High |
| Vector | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |