Debian Security Advisory
DSA-3433-1 samba -- security update
- Date Reported:
- 02 Jan 2016
- Affected Packages:
- Security database references:
- In Mitre's CVE dictionary: CVE-2015-3223, CVE-2015-5252, CVE-2015-5296, CVE-2015-5299, CVE-2015-5330, CVE-2015-7540, CVE-2015-8467.
- More information:
Several vulnerabilities have been discovered in Samba, a SMB/CIFS file, print, and login server for Unix. The Common Vulnerabilities and Exposures project identifies the following issues:
Thilo Uttendorfer of Linux Information Systems AG discovered that a malicious request can cause the Samba LDAP server to hang, spinning using CPU. A remote attacker can take advantage of this flaw to mount a denial of service.
YenyaKasprzak and the Computer Systems Unit team at Faculty of Informatics, Masaryk University discovered that insufficient symlink verification could allow data access outside an exported share path.
Stefan Metzmacher of SerNet discovered that Samba does not ensure that signing is negotiated when creating an encrypted client connection to a server. This allows a man-in-the-middle attacker to downgrade the connection and connect using the supplied credentials as an unsigned, unencrypted connection.
It was discovered that a missing access control check in the VFS shadow_copy2 module could allow unauthorized users to access snapshots.
Douglas Bagnall of Catalyst discovered that the Samba LDAP server is vulnerable to a remote memory read attack. A remote attacker can obtain sensitive information from daemon heap memory by sending crafted packets and then either read an error message, or a database value.
It was discovered that a malicious client can send packets that cause the LDAP server provided by the AD DC in the samba daemon process to consume unlimited memory and be terminated.
Andrew Bartlett of the Samba Team and Catalyst discovered that a Samba server deployed as an AD DC can expose Windows DCs in the same domain to a denial of service via the creation of multiple machine accounts. This issue is related to the MS15-096 / CVE-2015-2535 security issue in Windows.
For the oldstable distribution (wheezy), these problems have been fixed in version 2:3.6.6-6+deb7u6. The oldstable distribution (wheezy) is only affected by CVE-2015-5252, CVE-2015-5296 and CVE-2015-5299.
For the stable distribution (jessie), these problems have been fixed in version 2:4.1.17+dfsg-2+deb8u1. The fixes for CVE-2015-3223 and CVE-2015-5330 required an update to ldb 2:1.1.17-2+deb8u1 to correct the defects.
For the unstable distribution (sid), these problems have been fixed in version 2:4.1.22+dfsg-1. The fixes for CVE-2015-3223 and CVE-2015-5330 required an update to ldb 2:1.1.24-1 to correct the defects.
We recommend that you upgrade your samba packages.