All Samba versions 4.x.x before 4.9.17, 4.10.x before 4.10.11 and 4.11.x before 4.11.3 have an issue, where the (poorly named) dnsserver RPC pipe provides administrative facilities to modify DNS records and zones. Samba, when acting as an AD DC, stores DNS records in LDAP. In AD, the default permissions on the DNS partition allow creation of new records by authenticated users. This is used for example to allow machines to self-register in DNS. If a DNS record was created that case-insensitively matched the name of the zone, the ldb_qsort() and dns_name_compare() routines could be confused into reading memory prior to the list of DNS entries when responding to DnssrvEnumRecords() or DnssrvEnumRecords2() and so following invalid memory as a pointer.
https://www.samba.org/samba/security/CVE-2019-14861.html
https://security.netapp.com/advisory/ntap-20191210-0002/
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-14861
https://usn.ubuntu.com/4217-1/
https://usn.ubuntu.com/4217-2/
https://www.synology.com/security/advisory/Synology_SA_19_40
http://lists.opensuse.org/opensuse-security-announce/2019-12/msg00038.html
https://security.gentoo.org/glsa/202003-52
https://lists.debian.org/debian-lts-announce/2021/05/msg00023.html
Source: MITRE
Published: 2019-12-10
Updated: 2021-05-29
Type: CWE-276
Base Score: 3.5
Vector: AV:N/AC:M/Au:S/C:N/I:N/A:P
Impact Score: 2.9
Exploitability Score: 6.8
Severity: LOW
Base Score: 5.3
Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
Impact Score: 3.6
Exploitability Score: 1.6
Severity: MEDIUM