{"id":"UBUNTU-CVE-2018-16851","details":"Samba from version 4.0.0 and before versions 4.7.12, 4.8.7, 4.9.3 is vulnerable to a denial of service. 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.","modified":"2026-02-04T02:58:38.687235Z","published":"2018-11-27T00:00:00Z","related":["USN-3827-1","USN-3827-2"],"upstream":["CVE-2018-16851"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2018-16851"},{"type":"REPORT","url":"https://www.samba.org/samba/security/CVE-2018-16851.html"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-3827-1"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-3827-2"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2018-16851"}],"affected":[{"package":{"name":"samba","ecosystem":"Ubuntu:14.04:LTS","purl":"pkg:deb/ubuntu/samba@2:4.3.11+dfsg-0ubuntu0.14.04.19?arch=source&distro=trusty"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2:4.3.11+dfsg-0ubuntu0.14.04.19"}]}],"versions":["2:3.6.18-1ubuntu3","2:4.0.10+dfsg-4ubuntu2","2:4.0.13+dfsg-1ubuntu1","2:4.1.3+dfsg-2ubuntu2","2:4.1.3+dfsg-2ubuntu3","2:4.1.3+dfsg-2ubuntu4","2:4.1.3+dfsg-2ubuntu5","2:4.1.6+dfsg-1ubuntu1","2:4.1.6+dfsg-1ubuntu2","2:4.1.6+dfsg-1ubuntu2.14.04.1","2:4.1.6+dfsg-1ubuntu2.14.04.2","2:4.1.6+dfsg-1ubuntu2.14.04.3","2:4.1.6+dfsg-1ubuntu2.14.04.4","2:4.1.6+dfsg-1ubuntu2.14.04.5","2:4.1.6+dfsg-1ubuntu2.14.04.7","2:4.1.6+dfsg-1ubuntu2.14.04.8","2:4.1.6+dfsg-1ubuntu2.14.04.9","2:4.1.6+dfsg-1ubuntu2.14.04.11","2:4.1.6+dfsg-1ubuntu2.14.04.12","2:4.1.6+dfsg-1ubuntu2.14.04.13","2:4.3.8+dfsg-0ubuntu0.14.04.2","2:4.3.9+dfsg-0ubuntu0.14.04.1","2:4.3.9+dfsg-0ubuntu0.14.04.3","2:4.3.11+dfsg-0ubuntu0.14.04.1","2:4.3.11+dfsg-0ubuntu0.14.04.2","2:4.3.11+dfsg-0ubuntu0.14.04.3","2:4.3.11+dfsg-0ubuntu0.14.04.4","2:4.3.11+dfsg-0ubuntu0.14.04.6","2:4.3.11+dfsg-0ubuntu0.14.04.7","2:4.3.11+dfsg-0ubuntu0.14.04.8","2:4.3.11+dfsg-0ubuntu0.14.04.9","2:4.3.11+dfsg-0ubuntu0.14.04.10","2:4.3.11+dfsg-0ubuntu0.14.04.11","2:4.3.11+dfsg-0ubuntu0.14.04.12","2:4.3.11+dfsg-0ubuntu0.14.04.13","2:4.3.11+dfsg-0ubuntu0.14.04.14","2:4.3.11+dfsg-0ubuntu0.14.04.16","2:4.3.11+dfsg-0ubuntu0.14.04.17"],"ecosystem_specific":{"binaries":[{"binary_version":"2:4.3.11+dfsg-0ubuntu0.14.04.19","binary_name":"libnss-winbind"},{"binary_version":"2:4.3.11+dfsg-0ubuntu0.14.04.19","binary_name":"libpam-smbpass"},{"binary_version":"2:4.3.11+dfsg-0ubuntu0.14.04.19","binary_name":"libpam-winbind"},{"binary_version":"2:4.3.11+dfsg-0ubuntu0.14.04.19","binary_name":"libparse-pidl-perl"},{"binary_version":"2:4.3.11+dfsg-0ubuntu0.14.04.19","binary_name":"libsmbclient"},{"binary_version":"2:4.3.11+dfsg-0ubuntu0.14.04.19","binary_name":"libsmbclient-dev"},{"binary_version":"2:4.3.11+dfsg-0ubuntu0.14.04.19","binary_name":"libsmbsharemodes-dev"},{"binary_version":"2:4.3.11+dfsg-0ubuntu0.14.04.19","binary_name":"libsmbsharemodes0"},{"binary_version":"2:4.3.11+dfsg-0ubuntu0.14.04.19","binary_name":"libwbclient-dev"},{"binary_version":"2:4.3.11+dfsg-0ubuntu0.14.04.19","binary_name":"libwbclient0"},{"binary_version":"2:4.3.11+dfsg-0ubuntu0.14.04.19","binary_name":"python-samba"},{"binary_version":"2:4.3.11+dfsg-0ubuntu0.14.04.19","binary_name":"registry-tools"},{"binary_version":"2:4.3.11+dfsg-0ubuntu0.14.04.19","binary_name":"samba"},{"binary_version":"2:4.3.11+dfsg-0ubuntu0.14.04.19","binary_name":"samba-common"},{"binary_version":"2:4.3.11+dfsg-0ubuntu0.14.04.19","binary_name":"samba-common-bin"},{"binary_version":"2:4.3.11+dfsg-0ubuntu0.14.04.19","binary_name":"samba-dev"},{"binary_version":"2:4.3.11+dfsg-0ubuntu0.14.04.19","binary_name":"samba-dsdb-modules"},{"binary_version":"2:4.3.11+dfsg-0ubuntu0.14.04.19","binary_name":"samba-libs"},{"binary_version":"2:4.3.11+dfsg-0ubuntu0.14.04.19","binary_name":"samba-testsuite"},{"binary_version":"2:4.3.11+dfsg-0ubuntu0.14.04.19","binary_name":"samba-vfs-modules"},{"binary_version":"2:4.3.11+dfsg-0ubuntu0.14.04.19","binary_name":"smbclient"},{"binary_version":"2:4.3.11+dfsg-0ubuntu0.14.04.19","binary_name":"winbind"}],"availability":"No 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