Horizon Alert
Summary of the vulnerability and why it matters
The Apache Spark UI contains a vulnerability that could allow unauthorized users to execute arbitrary commands. This occurs when access control lists are enabled and a specific code path is triggered. The consequence is the potential for attackers to run commands on the system with the privileges of the Spark process.
- Apache Spark UI
- Command execution via arbitrary user input
- System compromise and data breaches
Attack Path
How an attacker could exploit the issue
Apache Spark's UI, when Access Control Lists (ACLs) are enabled, can allow an attacker to impersonate a user. This impersonation occurs through a specific code path in the `HttpSecurityFilter`. An attacker can then manipulate permission checks to construct and execute arbitrary Unix shell commands. This leads to the execution of commands with the privileges of the Spark user.
- Exposed Spark UI with ACLs enabled.
- Attacker provides an arbitrary username.
- Arbitrary shell command execution.
Live Threat
Current exploitation, exposure, and threat context
This vulnerability in Apache Spark allows for arbitrary command execution, potentially enabling attackers to compromise systems and access sensitive data. Attackers could exploit this by sending specially crafted input to the Spark UI, which, under certain conditions, can lead to the execution of malicious commands with the privileges of the Spark user. The potential for widespread impact and the severity of the exploit suggest that organizations should treat this as a high-priority issue.
- Likely requires low attacker skill.
- Requires network access and low privileges.
- Significant business risk and urgency.
Priority actions
Operational Fix
Recommended remediation, mitigation, and detection steps
An organization using Apache Spark should address a command injection vulnerability that allows unauthorized users to execute arbitrary shell commands. This risk can be mitigated by identifying affected systems, reducing their exposure, implementing vendor-provided fixes, and verifying the successful application of these fixes, followed by ongoing monitoring.
- Find exposed Spark assets.
- Limit network access to Spark UI.
- Apply vendor updates and validate.
- Monitor for related activity.
