CVE-2021-3738

In DCE/RPC it is possible to share the handles (cookies for resource state)
between multiple connections via a mechanism called ‘association groups’.
These handles can reference connections to our sam.ldb database. However
while the database was correctly shared, the user credentials state was
only pointed at, and when one connection within that association group
ended, the database would be left pointing at an invalid ‘struct
session_info’. The most likely outcome here is a crash, but it is possible
that the use-after-free could instead allow different user state to be
pointed at and this might allow more privileged access.

Bugs

• <https://bugzilla.samba.org/show_bug.cgi?id=14468&gt;

Notes