Horizon Alert
Summary of the vulnerability and why it matters
This advisory addresses a critical vulnerability in Grafana Image Renderer that could allow an attacker to execute arbitrary code on affected systems. The issue stems from improper validation of file paths, potentially enabling an attacker to write files to sensitive locations, which could then be loaded by the rendering process. This threat is significant if the system's authentication token is not secured or if the renderer endpoint is accessible.
- Remote code execution risk in Grafana.
- Executive attention needed for potential system compromise.
- Confirm relevance and exposure to Grafana usage.
Attack Path
How an attacker could exploit the issue
An attacker with low-privileged access could exploit this vulnerability by sending a crafted request to the Grafana Image Renderer's CSV rendering endpoint. This endpoint, lacking proper validation, allows the attacker to specify an arbitrary file path to save a shared object. When the Chromium process, used by the renderer, subsequently loads this object, it can lead to remote code execution.
- Requires network access and known credentials.
- Triggered by sending a malicious CSV render request.
- Allows remote code execution on the server.
Live Threat
Current exploitation, exposure, and threat context
When an attacker can reach the image renderer endpoint and the default authentication token is known, the system could allow an attacker to write files to arbitrary locations. This could lead to the Chromium process loading a malicious shared object, potentially enabling remote code execution within the affected Grafana Image Renderer instance.
- Arbitrary file write to system.
- Attacker reaches endpoint, uses known token.
- Potential for remote code execution.
Operational Fix
Recommended remediation, mitigation, and detection steps
The Grafana Image Renderer component, specifically the `/render/csv` endpoint, presents a critical remote code execution risk if its default authentication token is compromised and the endpoint is accessible. Owners of Grafana instances, likely falling under infrastructure, platform, or application teams, must first identify all deployments of the affected component. Confirming its reachability and business criticality will dictate the immediate priority, followed by coordinating with vendor management and planning remediation during a maintenance window or implementing temporary risk reduction measures.
- Identify Grafana Image Renderer deployments.
- Verify token security and endpoint reachability.
- Plan remediation or risk reduction.
