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1.110. krb5

1.110.1. RHSA-2010:0863: Important security update

Updated krb5 packages that fix one security issue are now available for Red Hat Enterprise Linux 6.
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 in the References section.
Kerberos is a network authentication system which allows clients and servers to authenticate to each other using symmetric encryption and a trusted third party, the Key Distribution Center (KDC).
An uninitialized pointer use flaw was found in the way the MIT Kerberos KDC handled TGS (Ticket-granting Server) request messages. A remote, authenticated attacker could use this flaw to crash the KDC or, possibly, disclose KDC memory or execute arbitrary code with the privileges of the KDC (krb5kdc). (CVE-2010-1322)
Red Hat would like to thank the MIT Kerberos Team for reporting this issue. Upstream acknowledges Mike Roszkowski as the original reporter.
All krb5 users should upgrade to these updated packages, which contain a backported patch to correct this issue. After installing the updated packages, the krb5kdc daemon will be restarted automatically.

1.110.2. RHSA-2010:0925: Important security and bug fix update

Updated krb5 packages that fix multiple security issues and one bug are now available for Red Hat Enterprise Linux 6.
The Red Hat Security Response Team has rated this update as having important security impact. Common Vulnerability Scoring System (CVSS) base scores, which give detailed severity ratings, are available for each vulnerability from the CVE links in the References section.
Kerberos is a network authentication system which allows clients and servers to authenticate to each other using symmetric encryption and a trusted third party, the Key Distribution Center (KDC).
Multiple checksum validation flaws were discovered in the MIT Kerberos implementation. A remote attacker could use these flaws to tamper with certain Kerberos protocol packets and, possibly, bypass authentication or authorization mechanisms and escalate their privileges. (CVE-2010-1323, CVE-2010-1324, CVE-2010-4020)
Red Hat would like to thank the MIT Kerberos Team for reporting these issues.
This update also fixes the following bug:
* When attempting to perform PKINIT pre-authentication, if the client had more than one possible candidate certificate the client could fail to select the certificate and key to use. This usually occurred if certificate selection was configured to use the value of the keyUsage extension, or if any of the candidate certificates did not contain a subjectAltName extension. Consequently, the client attempted to perform pre-authentication using a different (usually password-based) mechanism. (BZ#644825)
All krb5 users should upgrade to these updated packages, which contain backported patches to correct these issues. After installing the updated packages, the krb5kdc daemon will be restarted automatically.

1.110.3. RHSA-2011:0200: Important security update

Updated krb5 packages that fix three security issues are now available for Red Hat Enterprise Linux 6.
The Red Hat Security Response Team has rated this update as having important security impact. Common Vulnerability Scoring System (CVSS) base scores, which give detailed severity ratings, are available for each vulnerability from the CVE links in the References section.
Kerberos is a network authentication system which allows clients and servers to authenticate to each other using symmetric encryption and a trusted third-party, the Key Distribution Center (KDC).
A NULL pointer dereference flaw was found in the way the MIT Kerberos KDC processed principal names that were not null terminated, when the KDC was configured to use an LDAP back end. A remote attacker could use this flaw to crash the KDC via a specially-crafted request. (CVE-2011-0282)
A denial of service flaw was found in the way the MIT Kerberos KDC processed certain principal names when the KDC was configured to use an LDAP back end. A remote attacker could use this flaw to cause the KDC to hang via a specially-crafted request. (CVE-2011-0281)
A denial of service flaw was found in the way the MIT Kerberos V5 slave KDC update server (kpropd) processed certain update requests for KDC database propagation. A remote attacker could use this flaw to terminate the kpropd daemon via a specially-crafted update request. (CVE-2010-4022)
Red Hat would like to thank the MIT Kerberos Team for reporting the CVE-2011-0282 and CVE-2011-0281 issues. Upstream acknowledges Kevin Longfellow of Oracle Corporation as the original reporter of the CVE-2011-0281 issue.
All krb5 users should upgrade to these updated packages, which contain backported patches to correct these issues. After installing the updated packages, the krb5kdc daemon will be restarted automatically.

1.110.4. RHSA-2011:0356: Important security update

Updated krb5 packages that fix one security issue are now available for Red Hat Enterprise Linux 6.
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 in the References section.
Kerberos is a network authentication system which allows clients and servers to authenticate to each other using symmetric encryption and a trusted third-party, the Key Distribution Center (KDC). The Public Key Cryptography for Initial Authentication in Kerberos (PKINIT) capability provides support for using public-key authentication with Kerberos.
A double-free flaw was found in the way the MIT Kerberos KDC handled initial authentication requests (AS-REQ), when the KDC was configured to provide the PKINIT capability. A remote attacker could use this flaw to cause the KDC daemon to abort by using a specially-crafted AS-REQ request. (CVE-2011-0284)
All krb5 users should upgrade to these updated packages, which contain a backported patch to correct this issue. After installing the updated packages, the krb5kdc daemon will be restarted automatically.

1.110.5. RHSA-2011:0447: Moderate security update

Updated krb5 packages that fix one security issue are now available for Red Hat Enterprise Linux 6.
The Red Hat Security Response Team has rated this update as having moderate security impact. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available from the CVE link in the References section.
Kerberos is a network authentication system which allows clients and servers to authenticate to each other using symmetric encryption and a trusted third-party, the Key Distribution Center (KDC).
An invalid free flaw was found in the password-changing capability of the MIT Kerberos administration daemon, kadmind. A remote, unauthenticated attacker could use this flaw to cause kadmind to abort via a specially-crafted request. (CVE-2011-0285)
All krb5 users should upgrade to these updated packages, which contain a backported patch to correct this issue. After installing the updated packages, the kadmind daemon will be restarted automatically.

1.110.6. RHBA-2011:0571: bugfix update

Updated krb5 packages that fix multiple bugs are now available for Red Hat Enterprise Linux 6.
Kerberos is a network authentication system which allows clients and servers to authenticate to each other using symmetric encryption and a trusted third-party, the Key Distribution Center (KDC).
Kerberos has been upgraded to version 1.9, which provides a number of bug fixes over the previous version. (BZ#642417)
This update fixes the following bugs:
  • Previously, no IPv6 suport was available for kprop, kpropd, kadmin and kadmind. This update adds IPv6 support to these utilities. (BZ#595841, BZ#595842)
  • Previously, the krbPwdExpiration attribute in the principal's entry would often be ignored when the realm database was stored in a directory server. This update fixes this problem and this attribute is no longer ignored. (BZ#627039)
  • Previously, kinit with smart card login did not authenticate to the KDC correctly if the certificate on the smart card did not contain a subjectAltName extension or multiple certificates were available and krb5.conf was configured to select according to the value of the keyUsage extension in the certificates. This update continues to look for certificates with the right extension and corrects the valuation. (BZ#629022)
  • Previously, the init script for the kpropd was not Linux Standards Base (LSB) compliant. With this update, this init script is LSB compliant. (BZ#630587)
  • Previously, the KDC log files were not rotated by default. This update corrects this problem. Now these log files are rotated correctly. (BZ#630968)
  • Previously, logins failed if the user had a .k5login file which did not explicitly contain the user's principal name. With this update, this check can be disabled using the "k5login_authoritative" setting in krb5.conf. (BZ#646499)
  • Previously, GSSAPI authentication from Windows clients using cross-realm authentication failed if the client's ticket included a Privilege Attribute Certificate (PAC) with a failed signature check. Failed signature checks are now ignored. (BZ#679612)
All krb5 users are advised to upgrade to these updated packages, which fix these bugs.