Critical: samba security and bug fix update

Topic

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

Red Hat Product Security has rated this update as having a security impact of Critical. 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

Samba is an open-source implementation of the Server Message Block (SMB) protocol and the related Common Internet File System (CIFS) protocol, which allow PC-compatible machines to share files, printers, and various information.

Security Fix(es):

• samba: Out-of-bounds heap read/write vulnerability in VFS module vfs_fruit allows code execution (CVE-2021-44142)

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.

Bug Fix(es):

• Fix username map script regression introduced with CVE-2020-25717 (BZ#2046174)
• Fix possible segfault when joining the domain (BZ#2046160)

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 this update, the smb service will be restarted automatically.

Affected Products

• Red Hat Enterprise Linux for x86_64 8 x86_64
• Red Hat Enterprise Linux for IBM z Systems 8 s390x
• Red Hat Enterprise Linux for Power, little endian 8 ppc64le
• Red Hat Virtualization Host 4 for RHEL 8 x86_64
• Red Hat Enterprise Linux for ARM 64 8 aarch64
• Red Hat CodeReady Linux Builder for x86_64 8 x86_64
• Red Hat CodeReady Linux Builder for Power, little endian 8 ppc64le
• Red Hat CodeReady Linux Builder for ARM 64 8 aarch64
• Red Hat CodeReady Linux Builder for IBM z Systems 8 s390x

Fixes

• BZ - 2046146 - CVE-2021-44142 samba: Out-of-bounds heap read/write vulnerability in VFS module vfs_fruit allows code execution
• BZ - 2046160 - [smb] Segmentation fault when joining the domain [rhel-8.5.0.z]
• BZ - 2046174 - Failed to authenticate users after upgrade samba package to release samba-4.14.5-7x [rhel-8.5.0.z]

CVEs

• CVE-2021-44142

References

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