A flaw was found in samba versions 4.0.0 to 4.5.2. The Samba routine ndr_pull_dnsp_name contains an integer wrap problem, leading to an attacker-controlled memory overwrite. ndr_pull_dnsp_name parses data from the Samba Active Directory ldb database. Any user who can write to the dnsRecord attribute over LDAP can trigger this memory corruption. By default, all authenticated LDAP users can write to the dnsRecord attribute on new DNS objects. This makes the defect a remote privilege escalation.
A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc().
The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.
| Link | Tags |
|---|---|
| https://www.samba.org/samba/security/CVE-2016-2123.html | patch vendor advisory |
| http://www.securityfocus.com/bid/94970 | vdb entry third party advisory |
| https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2016-2123 | issue tracking |
| http://www.securitytracker.com/id/1037493 | vdb entry third party advisory |