Issued:

2021-09-21

Updated:

2021-09-21

RHSA-2021:3576 - Moderate: krb5 security update

Synopsis

Moderate: krb5 security update

Type/Severity

Security Advisory Moderate

Topic

An update for krb5 is now available for Red Hat Enterprise Linux 8.

Red Hat Product Security has rated this update as having a security impact of Moderate. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.

Description

Kerberos is a network authentication system, which can improve the security of your network by eliminating the insecure practice of sending passwords over the network in unencrypted form. It allows clients and servers to authenticate to each other with the help of a trusted third party, the Kerberos key distribution center (KDC).

Security Fix(es):

• krb5: Sending a request containing PA-ENCRYPTED-CHALLENGE padata element without using FAST could result in NULL dereference in KDC which leads to DoS (CVE-2021-36222)

• krb5: NULL pointer dereference in process_tgs_req() in kdc/do_tgs_req.c via a FAST inner body that lacks server field (CVE-2021-37750)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Solution

For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

After installing the updated packages, running Kerberos services (krb5kdc, kadmin, and kprop) will be restarted automatically.

Affected Products

Updated Packages

• krb5-libs-debuginfo-1.18.2-8.3.el8_4.x86_64.rpm
• krb5-devel-debuginfo-1.18.2-8.3.el8_4.x86_64.rpm
• krb5-workstation-1.18.2-8.3.el8_4.ppc64le.rpm
• krb5-pkinit-debuginfo-1.18.2-8.3.el8_4.ppc64le.rpm
• krb5-server-1.18.2-8.3.el8_4.s390x.rpm
• krb5-server-ldap-debuginfo-1.18.2-8.3.el8_4.i686.rpm
• krb5-server-debuginfo-1.18.2-8.3.el8_4.x86_64.rpm
• krb5-workstation-debuginfo-1.18.2-8.3.el8_4.x86_64.rpm
• libkadm5-1.18.2-8.3.el8_4.ppc64le.rpm
• krb5-pkinit-debuginfo-1.18.2-8.3.el8_4.aarch64.rpm
• krb5-pkinit-debuginfo-1.18.2-8.3.el8_4.s390x.rpm
• libkadm5-1.18.2-8.3.el8_4.s390x.rpm
• krb5-workstation-debuginfo-1.18.2-8.3.el8_4.i686.rpm
• libkadm5-debuginfo-1.18.2-8.3.el8_4.i686.rpm
• krb5-libs-1.18.2-8.3.el8_4.ppc64le.rpm
• krb5-server-ldap-1.18.2-8.3.el8_4.x86_64.rpm
• krb5-pkinit-1.18.2-8.3.el8_4.s390x.rpm
• libkadm5-debuginfo-1.18.2-8.3.el8_4.aarch64.rpm
• krb5-libs-1.18.2-8.3.el8_4.s390x.rpm
• libkadm5-debuginfo-1.18.2-8.3.el8_4.x86_64.rpm
• krb5-pkinit-debuginfo-1.18.2-8.3.el8_4.i686.rpm
• krb5-server-1.18.2-8.3.el8_4.ppc64le.rpm
• krb5-debuginfo-1.18.2-8.3.el8_4.x86_64.rpm
• krb5-workstation-1.18.2-8.3.el8_4.x86_64.rpm
• krb5-libs-1.18.2-8.3.el8_4.i686.rpm
• krb5-debugsource-1.18.2-8.3.el8_4.x86_64.rpm
• krb5-pkinit-1.18.2-8.3.el8_4.x86_64.rpm
• krb5-devel-1.18.2-8.3.el8_4.aarch64.rpm
• krb5-devel-1.18.2-8.3.el8_4.x86_64.rpm
• krb5-pkinit-1.18.2-8.3.el8_4.i686.rpm
• krb5-server-ldap-1.18.2-8.3.el8_4.i686.rpm
• krb5-libs-debuginfo-1.18.2-8.3.el8_4.i686.rpm
• krb5-server-ldap-debuginfo-1.18.2-8.3.el8_4.aarch64.rpm
• krb5-workstation-1.18.2-8.3.el8_4.s390x.rpm
• libkadm5-1.18.2-8.3.el8_4.x86_64.rpm
• krb5-devel-debuginfo-1.18.2-8.3.el8_4.i686.rpm
• krb5-server-1.18.2-8.3.el8_4.i686.rpm
• krb5-devel-1.18.2-8.3.el8_4.ppc64le.rpm
• krb5-devel-1.18.2-8.3.el8_4.s390x.rpm
• krb5-workstation-debuginfo-1.18.2-8.3.el8_4.s390x.rpm
• krb5-libs-debuginfo-1.18.2-8.3.el8_4.s390x.rpm
• krb5-server-1.18.2-8.3.el8_4.aarch64.rpm
• krb5-server-ldap-1.18.2-8.3.el8_4.aarch64.rpm
• krb5-workstation-1.18.2-8.3.el8_4.aarch64.rpm
• krb5-server-debuginfo-1.18.2-8.3.el8_4.ppc64le.rpm
• libkadm5-debuginfo-1.18.2-8.3.el8_4.ppc64le.rpm
• libkadm5-debuginfo-1.18.2-8.3.el8_4.s390x.rpm
• krb5-debuginfo-1.18.2-8.3.el8_4.s390x.rpm
• krb5-libs-debuginfo-1.18.2-8.3.el8_4.ppc64le.rpm
• krb5-debugsource-1.18.2-8.3.el8_4.ppc64le.rpm
• krb5-pkinit-1.18.2-8.3.el8_4.aarch64.rpm
• krb5-debugsource-1.18.2-8.3.el8_4.s390x.rpm
• krb5-devel-debuginfo-1.18.2-8.3.el8_4.ppc64le.rpm
• krb5-devel-debuginfo-1.18.2-8.3.el8_4.s390x.rpm
• krb5-libs-1.18.2-8.3.el8_4.aarch64.rpm
• krb5-server-ldap-debuginfo-1.18.2-8.3.el8_4.ppc64le.rpm
• krb5-workstation-debuginfo-1.18.2-8.3.el8_4.aarch64.rpm
• krb5-debuginfo-1.18.2-8.3.el8_4.i686.rpm
• krb5-server-1.18.2-8.3.el8_4.x86_64.rpm
• krb5-pkinit-debuginfo-1.18.2-8.3.el8_4.x86_64.rpm
• krb5-debuginfo-1.18.2-8.3.el8_4.aarch64.rpm
• krb5-server-ldap-1.18.2-8.3.el8_4.ppc64le.rpm
• krb5-workstation-debuginfo-1.18.2-8.3.el8_4.ppc64le.rpm
• krb5-debugsource-1.18.2-8.3.el8_4.aarch64.rpm
• krb5-libs-1.18.2-8.3.el8_4.x86_64.rpm
• krb5-debugsource-1.18.2-8.3.el8_4.i686.rpm
• krb5-devel-1.18.2-8.3.el8_4.i686.rpm
• krb5-devel-debuginfo-1.18.2-8.3.el8_4.aarch64.rpm
• krb5-server-ldap-debuginfo-1.18.2-8.3.el8_4.s390x.rpm
• libkadm5-1.18.2-8.3.el8_4.aarch64.rpm
• krb5-server-ldap-1.18.2-8.3.el8_4.s390x.rpm
• krb5-server-ldap-debuginfo-1.18.2-8.3.el8_4.x86_64.rpm
• krb5-server-debuginfo-1.18.2-8.3.el8_4.aarch64.rpm
• krb5-pkinit-1.18.2-8.3.el8_4.ppc64le.rpm
• libkadm5-1.18.2-8.3.el8_4.i686.rpm
• krb5-debuginfo-1.18.2-8.3.el8_4.ppc64le.rpm
• krb5-server-debuginfo-1.18.2-8.3.el8_4.i686.rpm
• krb5-server-debuginfo-1.18.2-8.3.el8_4.s390x.rpm
• krb5-1.18.2-8.3.el8_4.src.rpm
• krb5-libs-debuginfo-1.18.2-8.3.el8_4.aarch64.rpm

Fixes

• This content is not included.BZ - 1983720
• This content is not included.BZ - 1996834

CVEs

• CVE-2021-36222
• CVE-2021-37750

References

• https://access.redhat.com/security/updates/classification/#moderate

Additional information

• The Red Hat security contact is This content is not included.secalert@redhat.com. More contact details at https://access.redhat.com/security/team/contact/.
• Offline Security Data data is available for integration with other systems. See Offline Security Data API to get started.