CVE-2026-84828

Publication date 11 September 2026

Last updated 11 September 2026


Ubuntu priority

Description

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.

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Status

Package Ubuntu Release Status
pcs 26.04 LTS resolute
Vulnerable, fix deferred
24.04 LTS noble
Vulnerable, fix deferred
22.04 LTS jammy
Vulnerable, fix deferred
20.04 LTS focal
Not affected
18.04 LTS bionic
Not affected
16.04 LTS xenial
Not affected

Notes


mdeslaur

per Red Hat bug, introduced in 0.10.8 with: https://github.com/ClusterLabs/pcs/commit/9178b78d11baa70e700a5c0d9fc1c17f27d452fa The commit that fixes this issue is not public yet as of 2026-09-11, marking as deferred for now.

Patch details

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Package Patch details
pcs

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