CVE-2026-75889

Received Received - Intake

Grafana Alloy Local File Disclosure via ServiceMonitor

Publication date: 2026-08-27

Last updated on: 2026-08-27

Assigner: Grafana Labs

Description

Grafana Alloy’s prometheus.operator.servicemonitors component allows a user who can create or modify ServiceMonitor resources in a watched namespace to specify an arbitrary local file through bearerTokenFile. Alloy reads the file and sends its contents as a bearer token to an attacker-controlled scrape endpoint. This may disclose files accessible to the Alloy process, including its projected Kubernetes service account token, potentially granting the attacker Alloy’s Kubernetes permissions. Exploitation requires ServiceMonitor write access and lower privileges than Alloy’s service account.

CVSS Scores

EPSS Scores

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Meta Information

Published

2026-08-27

Last Modified

2026-08-27

Generated

2026-08-28

AI Q&A

2026-08-28

EPSS Evaluated

N/A

NVD

CVE-2026-75889

Affected Vendors & Products

Vendor	Product	Version / Range
grafana	alloy	*

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-UNKNOWN

Attack-Flow Graph

Executive Summary

Grafana Alloy’s prometheus.operator.servicemonitors component allows a user with ServiceMonitor write access to specify an arbitrary local file via bearerTokenFile. Alloy reads this file and sends its contents as a bearer token to a malicious scrape endpoint, potentially exposing sensitive files like Kubernetes service account tokens.

Detection Guidance

Check for ServiceMonitor resources with bearerTokenFile set to sensitive paths like /var/run/secrets/kubernetes.io/serviceaccount/token. Inspect Alloy logs for unexpected file reads or outbound connections to unknown endpoints.

Impact Analysis

An attacker with ServiceMonitor write access could exploit this to read sensitive files on the system where Alloy runs, including its Kubernetes service account token. This could grant the attacker Alloy’s Kubernetes permissions, leading to unauthorized access or control over the cluster.

Compliance Impact

This vulnerability could lead to unauthorized access to sensitive data, violating GDPR’s data protection requirements and HIPAA’s safeguards for protected health information. Organizations may face compliance breaches, legal penalties, and reputational damage if exploited.

Mitigation Strategies

Restrict ServiceMonitor creation/modification permissions to only necessary users. Update Grafana Alloy to the latest version. Review and remove any ServiceMonitor resources using bearerTokenFile.

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