Asterisk is an open source private branch exchange and telephony toolkit. Prior to Asterisk 20.20.1, 21.12.3, 22.10.1, 23.4.1 and Certified Asterisk 20.7-cert11, 22.8-cert3, `app_sms.c` copies externally controlled `SMS` lengths into `fixed in-struct buffers` without sufficient bounds checks, allowing an attacker to corrupt memory or crash Asterisk. The administrator must explicitly use the `SMS` dialplan application, which is useful when routing calls to or from `analog devices`, and must not have ensured that data passed to the application is valid. This issue is fixed in Asterisk 20.20.1, 21.12.3, 22.10.1, 23.4.1 and Certified Asterisk 20.7-cert11, 22.8-cert3.
https://github.com/asterisk/asterisk/tree/24.0.0-pre1
https://github.com/asterisk/asterisk/security/advisories/GHSA-q9fr-m7g8-6ph5
https://github.com/asterisk/asterisk/releases/tag/certified-22.8-cert3
https://github.com/asterisk/asterisk/releases/tag/certified-20.7-cert11
https://github.com/asterisk/asterisk/releases/tag/23.4.1
https://github.com/asterisk/asterisk/releases/tag/22.10.1
https://github.com/asterisk/asterisk/releases/tag/21.12.3
https://github.com/asterisk/asterisk/releases/tag/20.20.1
https://github.com/asterisk/asterisk/commit/f46f63bd4d33665d336cf8b5998650b915222549
https://github.com/asterisk/asterisk/commit/7048a3841df99e090b9d87246600373581629c98
https://github.com/asterisk/asterisk/commit/661d6a2fc5cc7744ab9d849ed3c73ae5066386df
https://github.com/asterisk/asterisk/commit/60f4ef3deac6b9af30519b46c13f103264038b82
https://github.com/asterisk/asterisk/commit/59b74276f24ba104d859f3f05897c9b8d835a28a
https://github.com/asterisk/asterisk/commit/38a2059eb77a91a6b6e76eeba5875c2b96027368
https://github.com/asterisk/asterisk/commit/15c66022dc441ec63d7bd5f53cf7f35db72964be
Published: 2026-10-27
Updated: 2026-10-28
Base Score: 6.4
Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:N/A:P
Severity: Medium
Base Score: 8.1
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
Severity: High
Base Score: 2.3
Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
Severity: Low
EPSS: 0.00481