samba4: security bump to version 4.8.7
Fixes the following security vulnerabilities:
- CVE-2018-14629:
All versions of Samba from 4.0.0 onwards are vulnerable to infinite
query recursion caused by CNAME loops. Any dns record can be added via
ldap by an unprivileged user using the ldbadd tool, so this is a
security issue.
- CVE-2018-16841:
When configured to accept smart-card authentication, Samba's KDC will call
talloc_free() twice on the same memory if the principal in a validly signed
certificate does not match the principal in the AS-REQ.
This is only possible after authentication with a trusted certificate.
talloc is robust against further corruption from a double-free with
talloc_free() and directly calls abort(), terminating the KDC process.
There is no further vulnerability associated with this issue, merely a
denial of service.
- CVE-2018-16851:
During the processing of an LDAP search before Samba's AD DC returns
the LDAP entries to the client, the entries are cached in a single
memory object with a maximum size of 256MB. When this size is
reached, the Samba process providing the LDAP service will follow the
NULL pointer, terminating the process.
There is no further vulnerability associated with this issue, merely a
denial of service.
- CVE-2018-16853:
A user in a Samba AD domain can crash the KDC when Samba is built in the
non-default MIT Kerberos configuration.
With this advisory we clarify that the MIT Kerberos build of the Samba
AD DC is considered experimental. Therefore the Samba Team will not
issue security patches for this configuration.
For more details, see the release notes:
https://www.samba.org/samba/history/samba-4.8.7.html
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
Peter Korsgaard