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, the LDAP realtime driver `res_config_ldap` may permit `LDAP filter injection` through a `SIP username`, allowing an unauthenticated attacker to make arbitrary LDAP queries using carefully crafted SIP packets and disclose information. The `res_config_ldap` module must be loaded and configured to access an LDAP server, which is not the default. 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-r6c2-hwc2-j4mp
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/ef280572a034cac3994075298facb1999778ee0d
https://github.com/asterisk/asterisk/commit/dd0c768d9e9678e4cb1ed95689a254a61452239b
https://github.com/asterisk/asterisk/commit/8170a6bfa75994e7617a8b9d7fe7a7140b70cbe2
https://github.com/asterisk/asterisk/commit/7e1ae09594a101950398cc6aff2dd2e5ab314884
https://github.com/asterisk/asterisk/commit/23c01b6d359c5d85da725beea89e394a6c031c5d
https://github.com/asterisk/asterisk/commit/14968f2f440ea0dd983caa4f477237a5224904dd
https://github.com/asterisk/asterisk/commit/04aa482212e43b292817444eb4de35499f4b1568
Published: 2026-10-26
Updated: 2026-10-27
Base Score: 5
Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:N/A:N
Severity: Medium
Base Score: 7.5
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Severity: High
Base Score: 6.9
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
Severity: Medium
EPSS: 0.01963