A NULL pointer dereference, or possible use-after-free flaw was found in Samba AD LDAP server in versions before 4.10.17, before 4.11.11 and before 4.12.4. Although some versions of Samba shipped with Red Hat Enterprise Linux do not support Samba in AD mode, the affected code is shipped with the libldb package. This flaw allows an authenticated user to possibly trigger a use-after-free or NULL pointer dereference. The highest threat from this vulnerability is to system availability.
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 Any operations using the original pointer are no longer valid because the memory “belongs” to the code that operates on the new pointer.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Samba | Samba | 4.5.0 (including) | 4.10.17 (excluding) |
| Samba | Samba | 4.11.0 (including) | 4.11.11 (excluding) |
| Samba | Samba | 4.12.0 (including) | 4.12.4 (excluding) |
| Red Hat Enterprise Linux 8 | RedHat | libldb-0:2.1.3-2.el8 | * |
| Red Hat Gluster Storage 3.5 for RHEL 7 | RedHat | samba-0:4.11.6-107.el7rhgs | * |
| Red Hat Gluster Storage 3.5 for RHEL 8 | RedHat | samba-0:4.11.6-107.el8rhgs | * |
| Samba | Ubuntu | bionic | * |
| Samba | Ubuntu | devel | * |
| Samba | Ubuntu | eoan | * |
| Samba | Ubuntu | esm-infra/bionic | * |
| Samba | Ubuntu | esm-infra/focal | * |
| Samba | Ubuntu | focal | * |
| Samba | Ubuntu | trusty | * |
| Samba | Ubuntu | upstream | * |