Asterisk: Stack buffer overflow in res_xmpp XMPP namespace prefix handling

Summary

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 authenticated attacker may cause a stack buffer overflow in `res_xmpp` `XMPP namespace prefix` handling using carefully crafted packets. The `res_xmpp` module must be loaded, an XMPP connection must be configured in `xmpp.conf`, and the attacker must have an XMPP account on the same or a federated server. 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.

Remediation

1. Inventory every asterisk asterisk deployment, including staging.
2. No fixed version appears in the public sources yet. Check the references below and the vendor directly.

References

• Referencehttps://github.com/asterisk/asterisk/security/advisories/GHSA-mxgm-8c6f-5p8f
• Referencehttps://github.com/asterisk/asterisk/commit/12072a559f592736a44dd9fbe1594e84714edfb4
• Referencehttps://github.com/asterisk/asterisk/commit/1328dbb503da4aa11a480a9c28e170f17e5f4e84
• Referencehttps://github.com/asterisk/asterisk/commit/3c4b08cf94eeaa3faefb3ae6c2d6ce1bd9747a13
• Referencehttps://github.com/asterisk/asterisk/commit/433102c16b8edfc31d28c96166fef03fe72fb923
• Referencehttps://github.com/asterisk/asterisk/commit/5e626250628b2579530f3f17e7b0aa37d082873b
• Referencehttps://github.com/asterisk/asterisk/commit/d570a85e45153a36919ace5d0ab06a195b30f9d1
• Referencehttps://github.com/asterisk/asterisk/commit/e329a6803ac5214028f98cc5f0b7167d66e32c08
• Referencehttps://github.com/asterisk/asterisk/releases/tag/20.20.1
• Referencehttps://github.com/asterisk/asterisk/releases/tag/21.12.3
• Referencehttps://github.com/asterisk/asterisk/releases/tag/22.10.1
• Referencehttps://github.com/asterisk/asterisk/releases/tag/23.4.1