An updated ipa-client package that fixes one security issue is now available for Red Hat Enterprise Linux 5.
The Red Hat Security Response Team has rated this update as having important security impact. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available from the CVE link associated with the description below.
Red Hat Identity Management is a centralized authentication, identity management and authorization solution for both traditional and cloud-based enterprise environments.
- A weakness was found in the way IPA clients communicated with IPA servers when initially attempting to join IPA domains. As there was no secure way to provide the IPA server's Certificate Authority (CA) certificate to the client during a join, the IPA client enrollment process was susceptible to man-in-the-middle attacks. This flaw could allow an attacker to obtain access to the IPA server using the credentials provided by an IPA client, including administrative access to the entire domain if the join was performed using an administrator's credentials.Note: This weakness was only exposed during the initial client join to the realm, because the IPA client did not yet have the CA certificate of the server. Once an IPA client has joined the realm and has obtained the CA certificate of the IPA server, all further communication is secure. If a client were using the OTP (one-time password) method to join to the realm, an attacker could only obtain unprivileged access to the server (enough to only join the realm).
Red Hat would like to thank Petr Menšík for reporting this issue.
When a fix for this flaw has been applied to the client but not yet the server, ipa-client-install, in unattended mode, will fail if you do not have the correct CA certificate locally, noting that you must use the "--force" option to insecurely obtain the certificate. In interactive mode, the certificate will try to be obtained securely from LDAP. If this fails, you will be prompted to insecurely download the certificate via HTTP. In the same situation when using OTP, LDAP will not be queried and you will be prompted to insecurely download the certificate via HTTP.
Users of ipa-client are advised to upgrade to this updated package, which corrects this issue.
Updated ipa-client packages that fix several bugs and add various enhancements are now available for Red Hat Enterprise Linux 5.
IPA (Identity, Policy, Audit) is an integrated solution to provide centrally managed identity, that is, machine, user, virtual machines, groups, and authentication credentials. The ipa-client package provides a tool to enroll a machine to an IPA version 2 server.
- If the IPA CA (Certification Authority) could not be added to the shared NSS database in the /etc/pki/nssdb/ directory, the client installer terminated unexpectedly with a fatal error message. The location of the directory has been fixed and the client installer no longer crashes.
- Due to a missing dependency on the pyOpenSSL package, installation of the ipa-client package failed. The missing dependency has been added and ipa-client can now be installed as expected.
- In some cases, a CA certificate was stored in the base64-encoded form (PEM) instead of the binary form (DER). The wrong CA format caused ipa-client to act as if no CA was available and the system enrollment to terminate unexpectedly. The ipa-client-install utility has been fixed to make the client more flexible and be able to handle the data stored in either format. As a result, the system enrollment as an IPA client now succeeds.
- Due to a bug, if one of the IPA masters was unavailable during enrollment, the ipa-client-install did not fail over to another master. Consequently, the ipa-client installation terminated unexpectedly. This bug has been fixed, and ipa-client-install now fails over to a functional replica as expected.
- Previously, there was more than one code path where a cleanup routine could be called. If the xmlrpc_env_clean() function preceded the initializing xmlrpc_env_init() function, the unenrolling of a client could fail. The order of the calls in xmlrpc-c has been edited and unenrolling a client no longer fails.
- In some cases, if replication between two IPA masters was slow, there was a short time period where the client was not known to one of the masters. Consequently, the kinit utility failed. The installation process has been reordered so that all operations are done against the same master the enrollment is initiated with.
Users of ipa-client are advised to upgrade to these updated packages, which fix these bugs.