Public vulnerability disclosure

CVE-2026-84828

Pcs: pcs: non-root haclient users can read arbitrary files via pcs host auth --token

publishedCWE-732

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.

Technical severity6.5 mediumCVSS 3.1 · CNA: redhat
Published2026-09-10Source updated 2026-11-06
Collected2026-11-062 attributed sources

Fixes and workarounds

Workaround

Restrict membership in the 'haclient' group to only trusted users who require cluster management access. Audit current 'haclient' group membership and remove any unnecessary accounts. This reduces exposure but does not fully eliminate the risk for legitimate haclient members.

Source: CNA: redhat

Affected products and versions

Affected products, source version ranges and reporting authorities
ProductVersionsAuthority
Red Hat Enterprise Linux 10
Red Hat
pcs
https://access.redhat.com/downloads/content/package-browser/
Range not reported
Other versions: affected
CNA: redhat
Red Hat Enterprise Linux 8
Red Hat
pcs
https://access.redhat.com/downloads/content/package-browser/
Range not reported
Other versions: affected
CNA: redhat
Red Hat Enterprise Linux 9
Red Hat
pcs
https://access.redhat.com/downloads/content/package-browser/
Range not reported
Other versions: affected
CNA: redhat
Red Hat OpenShift Container Platform 4
Red Hat
openshift/ose-rhel-coreos-9
https://access.redhat.com/downloads/content/package-browser/
Range not reported
Other versions: affected
CNA: redhat
Red Hat OpenShift Container Platform 5
Red Hat
openshift/ose-rhel-coreos-9
https://access.redhat.com/downloads/content/package-browser/
Range not reported
Other versions: affected
CNA: redhat
Red Hat OpenStack Platform 16.2
Red Hat
rhosp-rhel8/openstack-base
https://access.redhat.com/downloads/content/package-browser/
Range not reported
Other versions: affected
CNA: redhat
Red Hat OpenStack Platform 17.1
Red Hat
rhosp-rhel9/openstack-frr
https://access.redhat.com/downloads/content/package-browser/
Range not reported
Other versions: affected
CNA: redhat

Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.

CVSS assessments

CVSS scores, vectors and reporting authorities
Version / scoreVectorAuthority
3.1 / 6.5
medium
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:NCNA: redhat

Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

References

For agents and automation

Read public disclosures for free as Markdown or JSON. Compatible browsers also expose native WebMCP tools to search disclosures, read this page, and discover API access.

Use the ontology-linked Cyber API with x402 pay per request, or a Y2 Pro or Elite API key with the intel:cyber scope.

Endpoints and access details

https://api.y2.dev/api/v2/cyber/cves
https://api.y2.dev/api/v2/cyber/cves/{cveId}

A workspace owner or admin can create a Pro or Elite API key. Send Authorization: Bearer <Y2_API_KEY> from your trusted agent runtime.

For x402, omit Authorization and read the HTTP 402 payment challenge before signing a retry. Public browser tools do not make payments.

Agent access JSON · OpenAPI · CVE API guide