RHSA-2020:5609 - Security Advisory

Topic

An update for fapolicyd is now available for Red Hat Enterprise Linux 8.1 Extended Update Support.

Description

The fapolicyd software framework introduces a form of file access control based on a user-defined policy. The application file access control feature provides one of the most efficient ways to prevent running untrusted and possibly malicious applications on the system.

Bug Fix:

• When an update replaces the binary of a running application, the kernel modifies the application binary path in memory by appending the " (deleted)" suffix. Previously, the fapolicyd file access policy daemon treated such applications as untrusted, and prevented them from opening and executing any other files. As a consequence, the system was sometimes unable to boot after applying updates.

With this update, fapolicyd ignores the suffix in the binary path so the binary can match the trust database. As a result, fapolicyd enforces the rules correctly and the update process can finish.

(BZ#1906474)

Note: The issue from BZ#1906474 was previously addressed in erratum RHBA-2020:5241 linked to from the References section. Due to the high impact of the issue that can cause systems to become unable to boot, we are releasing the same fix again in a security erratum to ensure proper visibility to users who only install security updates. This fix has not been changed in any way since the original bug fix erratum. This erratum does not provide any security fixes.

For more details about the issue, see the Knowledgebase article linked from 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

Affected Products

• Red Hat Enterprise Linux for x86_64 - Extended Update Support 8.1 x86_64
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 8.1 s390x
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 8.1 ppc64le
• Red Hat Enterprise Linux for ARM 64 - Extended Update Support 8.1 aarch64
• Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 8.1 ppc64le
• Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 8.1 x86_64

Fixes

• BZ - 1906474 - Erratum RHBA-2020:4969 is of no help when upgrading partially RHEL 8.2 systems [rhel-8.1.0.z]

CVEs

(none)

References

• https://access.redhat.com/security/updates/classification/#important
• https://access.redhat.com/errata/RHBA-2020:5241
• https://access.redhat.com/solutions/5542661