# CVE-2026-84828: pcs: A flaw was found in PCS (Pacemaker Configuration System)

CVE-2026-84828 is fixed in pcs on 1 platform by DEBIAN-CVE-2026-84828 (version 0.12.3.1-1), released September 20, 2026. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2026-84828
- Priority: Routine
- CVSS: 6.5 (medium)
- EPSS: 0.0014
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Sep 10, 2026

## 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.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | pcs Debian 14 | 0.12.3.1-1 | [DEBIAN-CVE-2026-84828](https://patchblox.com/security/data/fix/linux/debian-cve-2026-84828.md) | Sep 20, 2026 |

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Data as of 2026-11-09T07:25:28Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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