ns-slapd in 389 Directory Server before 1.3.0.8 allows remote attackers to cause a denial of service (server crash) via a crafted Distinguished Name (DN) in a MOD operation request.

It was found that the 389 Directory Server did not properly restrict access to entries when the 'nsslapd-allow-anonymous-access' configuration setting is set to 'rootdse'. An anonymous user could connect to the LDAP database and, if the search scope is set to BASE, obtain access to information outside of the rootDSE. The 'rootdse' option exists to provide anonymous access to the rootDSE but no other entries in the directory. An administrator could believe that directory entries are being restricted with this option enabled, however the information provided would be the same as if 'nsslapd-allow-anonymous-access' were set to 'on'.

ACI's are still properly evaluated despite this flaw, so this can easily be mitigated by removing the anonymous read ACL.

IssueDescription:

It was found that when replication was enabled for each attribute in Red Hat Directory Server / 389 Directory Server, which is the default configuration, the server returned replicated metadata when the directory was searched while debugging was enabled. A remote attacker could use this flaw to disclose potentially sensitive information.

Acknowledgements:

This issue was discovered by Ludwig Krispenz of Red Hat.