Description
Grafana Image Renderer is vulnerable to remote code execution due to an arbitrary file write vulnerability. This is due to the fact that the /render/csv endpoint lacked validation of the filePath parameter that allowed an attacker to save a shared object to an arbitrary location that is then loaded by the Chromium process. Instances are vulnerable if: 1. The default token ("authToken") is not changed, or is known to the attacker. 2. The attacker can reach the image renderer endpoint. This issue affects grafana-image-renderer: from 1.0.0 through 4.0.16.
EPSS Score:
0%
Comprehensive Technical Analysis of EUVD-2025-33321
1. Vulnerability Assessment and Severity Evaluation
The vulnerability described in EUVD-2025-33321 pertains to the Grafana Image Renderer, specifically affecting versions from 1.0.0 through 4.0.16. The issue arises from an arbitrary file write vulnerability in the /render/csv endpoint, which lacks proper validation of the filePath parameter. This allows an attacker to save a shared object to an arbitrary location, which is then loaded by the Chromium process, leading to remote code execution (RCE).
Severity Evaluation:
- CVSS Base Score: 9.9 (Critical)
- CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
The high base score indicates a critical vulnerability due to the potential for complete system compromise, including confidentiality, integrity, and availability impacts. The attack vector is network-based (AV:N), requires low complexity (AC:L), and necessitates low privileges (PR:L) with no user interaction (UI:N). The scope change (S:C) further amplifies the impact.
2. Potential Attack Vectors and Exploitation Methods
Attack Vectors:
- Network Access: The attacker needs network access to the Grafana Image Renderer endpoint.
- Authentication Token: The attacker must know the default token ("authToken") or it must not have been changed from its default value.
Exploitation Methods:
- Arbitrary File Write: The attacker can exploit the lack of validation in the
filePathparameter to write a shared object to a specific location. - Code Execution: The shared object can then be loaded by the Chromium process, allowing the attacker to execute arbitrary code on the system.
3. Affected Systems and Software Versions
Affected Software:
- Grafana Image Renderer versions from 1.0.0 through 4.0.16.
Affected Systems:
- Any system running the vulnerable versions of Grafana Image Renderer, particularly those with the default "authToken" unchanged or known to the attacker.
4. Recommended Mitigation Strategies
- Update Software: Immediately update to Grafana Image Renderer version 4.0.17 or later, which addresses this vulnerability.
- Change Default Token: Ensure that the "authToken" is changed from its default value to a strong, unique token.
- Network Segmentation: Implement network segmentation to limit access to the Grafana Image Renderer endpoint.
- Access Controls: Enforce strict access controls and authentication mechanisms to prevent unauthorized access.
- Monitoring and Logging: Implement robust monitoring and logging to detect and respond to any suspicious activities related to the
/render/csvendpoint.
5. Impact on European Cybersecurity Landscape
The vulnerability poses a significant risk to organizations using Grafana for monitoring and visualization, particularly those in critical infrastructure sectors such as healthcare, finance, and energy. The potential for remote code execution can lead to data breaches, service disruptions, and other severe security incidents. Given the widespread use of Grafana, this vulnerability underscores the importance of timely patching and proactive security measures in the European cybersecurity landscape.
6. Technical Details for Security Professionals
Vulnerability Details:
- Endpoint:
/render/csv - Parameter:
filePath - Exploit Mechanism: Lack of validation allows arbitrary file write, leading to shared object loading and RCE.
Detection and Response:
- Intrusion Detection Systems (IDS): Configure IDS to monitor for unusual traffic patterns to the
/render/csvendpoint. - File Integrity Monitoring (FIM): Implement FIM to detect unauthorized changes to critical files and directories.
- Incident Response Plan: Develop and maintain an incident response plan tailored to handle RCE vulnerabilities, including steps for containment, eradication, and recovery.
References:
By addressing this vulnerability promptly and implementing robust security measures, organizations can mitigate the risk of exploitation and maintain the integrity of their systems.