Medium: krb5

Issue Overview:

A flaw was found in krb5. The Key Distribution Center (KDC) in MIT Kerberos 5 has a NULL pointer dereference via a FAST inner body that lacks a server field. An authenticated attacker could use this flaw to crash the Kerberos KDC server. The highest threat from this vulnerability is to system availability. (CVE-2021-37750)

Affected Packages:

krb5

Note:

This advisory is applicable to Amazon Linux 2 (AL2) Core repository. Visit this FAQ section for the difference between AL2 Core and AL2 Extras advisories.

Issue Correction:
Run yum update krb5 to update your system.

New Packages:

aarch64:  
    krb5-devel-1.15.1-37.amzn2.2.4.aarch64  
    krb5-libs-1.15.1-37.amzn2.2.4.aarch64  
    krb5-server-1.15.1-37.amzn2.2.4.aarch64  
    krb5-server-ldap-1.15.1-37.amzn2.2.4.aarch64  
    krb5-workstation-1.15.1-37.amzn2.2.4.aarch64  
    krb5-pkinit-1.15.1-37.amzn2.2.4.aarch64  
    libkadm5-1.15.1-37.amzn2.2.4.aarch64  
    krb5-debuginfo-1.15.1-37.amzn2.2.4.aarch64  
  
i686:  
    krb5-devel-1.15.1-37.amzn2.2.4.i686  
    krb5-libs-1.15.1-37.amzn2.2.4.i686  
    krb5-server-1.15.1-37.amzn2.2.4.i686  
    krb5-server-ldap-1.15.1-37.amzn2.2.4.i686  
    krb5-workstation-1.15.1-37.amzn2.2.4.i686  
    krb5-pkinit-1.15.1-37.amzn2.2.4.i686  
    libkadm5-1.15.1-37.amzn2.2.4.i686  
    krb5-debuginfo-1.15.1-37.amzn2.2.4.i686  
  
src:  
    krb5-1.15.1-37.amzn2.2.4.src  
  
x86_64:  
    krb5-devel-1.15.1-37.amzn2.2.4.x86_64  
    krb5-libs-1.15.1-37.amzn2.2.4.x86_64  
    krb5-server-1.15.1-37.amzn2.2.4.x86_64  
    krb5-server-ldap-1.15.1-37.amzn2.2.4.x86_64  
    krb5-workstation-1.15.1-37.amzn2.2.4.x86_64  
    krb5-pkinit-1.15.1-37.amzn2.2.4.x86_64  
    libkadm5-1.15.1-37.amzn2.2.4.x86_64  
    krb5-debuginfo-1.15.1-37.amzn2.2.4.x86_64  

Additional References

Red Hat: CVE-2021-37750

Mitre: CVE-2021-37750