PCS: Local File Disclosure via pcs host auth --token
CVE-2026-84828 Published on September 10, 2026
Pcs: pcs: non-root haclient users can read arbitrary files via pcs host auth --token
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.
Vulnerability Analysis
CVE-2026-84828 is exploitable with local system access, and requires small amount of user privileges. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have a high impact on confidentiality, with no impact on integrity and availability.
Timeline
Reported to Red Hat.
Made public. 9 days later.
Weakness Type
Incorrect Permission Assignment for Critical Resource
The product specifies permissions for a security-critical resource in a way that allows that resource to be read or modified by unintended actors. When a resource is given a permissions setting that provides access to a wider range of actors than required, it could lead to the exposure of sensitive information, or the modification of that resource by unintended parties. This is especially dangerous when the resource is related to program configuration, execution or sensitive user data.
Products Associated with CVE-2026-84828
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