A use-after-free in res_pjsip_pubsub.c in Sangoma Asterisk 16.28, 18.14, 19.6, and certified/18.9-cert2 may allow a remote authenticated attacker to crash Asterisk (denial of service) by performing activity on a subscription via a reliable transport at the same time that Asterisk is also performing activity on that subscription.
Weakness
The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory “belongs” to the code that operates on the new pointer.
Affected Software
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Asterisk | Sangoma | 16.0.0 (including) | 16.29.1 (excluding) |
| Asterisk | Sangoma | 18.14.0 (including) | 18.15.1 (excluding) |
| Asterisk | Sangoma | 19.6.0 (including) | 19.7.1 (excluding) |
| Asterisk | Sangoma | 20.0.0 (including) | 20.0.0 (including) |
| Certified_asterisk | Sangoma | 18.9-cert2 (including) | 18.9-cert2 (including) |
| Asterisk | Ubuntu | bionic | * |
| Asterisk | Ubuntu | focal | * |
| Asterisk | Ubuntu | kinetic | * |
| Asterisk | Ubuntu | lunar | * |
| Asterisk | Ubuntu | mantic | * |
| Asterisk | Ubuntu | oracular | * |
| Asterisk | Ubuntu | plucky | * |
| Asterisk | Ubuntu | trusty | * |
| Asterisk | Ubuntu | xenial | * |
Potential Mitigations
References
- https://downloads.asterisk.org/pub/security/AST-2022-008.html
- https://lists.debian.org/debian-lts-announce/2023/02/msg00029.html
- https://www.debian.org/security/2023/dsa-5358
- https://downloads.asterisk.org/pub/security/AST-2022-008.html
- https://lists.debian.org/debian-lts-announce/2023/02/msg00029.html
- https://www.debian.org/security/2023/dsa-5358