CVE-2026-84828
Pcs: pcs: non-root haclient users can read arbitrary files via pcs host auth --token
What happened?
A flaw was found in PCS (Pacemaker Configuration System). A local attacker with membership in the 'haclient' group can exploit the 'pcs host auth --token' command to read the contents of arbitrary files on the filesystem, provided the files are shorter than 256 bytes. The file contents are read with root privileges by the pcsd daemon and can be exfiltrated by the attacker through subsequent cluster node communication. This allows disclosure of sensitive data such as API keys, tokens, or configuration secrets that would otherwise be inaccessible to the attacker.
Affected software and versions
| Software | Version information | Fixed version |
|---|---|---|
| pcsRed Hat | Default status: affected | See vendor advisory |
| pcsRed Hat | Default status: affected | See vendor advisory |
| pcsRed Hat | Default status: affected | See vendor advisory |
| openshift/ose-rhel-coreos-9Red Hat | Default status: affected | See vendor advisory |
| openshift/ose-rhel-coreos-9Red Hat | Default status: affected | See vendor advisory |
| rhosp-rhel8/openstack-baseRed Hat | Default status: affected | See vendor advisory |
| rhosp-rhel9/openstack-frrRed Hat | Default status: affected | See vendor advisory |
Version information comes from the source record and can include unaffected products and exceptions. Distribution packages may contain backported fixes: an older upstream version alone does not prove a server is affected.
Is it being exploited?
This CVE was not listed in the CISA catalogue at our last retrieval. This does not establish that exploitation is absent.
How to respond
- Confirm the product, installed package version, and any configuration requirements in the vendor advisory.
- Follow the vendor’s remediation or workaround guidance in the references below. Structured fixed-version data is unavailable here; the publisher’s description may include a fix or workaround.
- Restart affected services if required, then verify the running version. Known exploitation may warrant investigation as well as patching.