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, an out-of-bounds write in `chan_unistim` `DIALPAGE` digit handling can overflow the `phone_number` field and crash Asterisk when an attacker sends a carefully crafted incoming request packet. The `chan_unistim` module must be loaded and configured with a valid `UNISTIM UDP port` that the attacker can reach. The attacker must register as a configured `phone MAC`, or the deployment must have an equivalent `production/autoprovisioning` path that allows the client to reach the main page. 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-3g56-cgrh-95p5
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/ff65e4b0867bee12cdcb3a6219b976ee7ee08963
https://github.com/asterisk/asterisk/commit/fc3a1cb3c386c962bfca8cd9d533d1390d4ad933
https://github.com/asterisk/asterisk/commit/d803b5370b05f39a6241b2556eb9894b02148e6a
https://github.com/asterisk/asterisk/commit/ce6e2233599b76bc30c33b4816b15609c8ddc8b6
https://github.com/asterisk/asterisk/commit/6f414ec771eaa3318a4b2d28f70fa387196ae283
https://github.com/asterisk/asterisk/commit/6da8e10c210d8e014c27c67235252e1dfc794446
https://github.com/asterisk/asterisk/commit/430f423c84e4e32a462d907632b66c9793236e96