Debian: DSA-4791-1: Pacemaker Critical IPC Bypass Advisory

Ken Gaillot discovered a vulnerability in the Pacemaker cluster
resource manager: If ACLs were configured for users in the "haclient"
group, the ACL restrictions could be bypassed via unrestricted IPC
communication, resulting in cluster-wide arbitrary code execution with
root privileges.

If the "enable-acl" cluster option isn't enabled, members of the
"haclient" group can modify Pacemaker's Cluster Information Base without
restriction, which already gives them these capabilities, so there is
no additional exposure in such a setup.

For the stable distribution (buster), this problem has been fixed in
version 2.0.1-5+deb10u1.

We recommend that you upgrade your pacemaker packages.

For the detailed security status of pacemaker please refer to
its security tracker page at:
https://security-tracker.debian.org/tracker/source-package/pacemaker

Further information about Debian Security Advisories, how to apply
these updates to your system and frequently asked questions can be
found at: https://www.debian.org/...