CVE-2024-9413 Overview
CVE-2024-9413 is a buffer overflow vulnerability in the transport_message_handler function of Arm System Control Processor (SCP) Firmware. The flaw stems from improper error handling [CWE-755] in release versions 2.11.0 through 2.15.0. An Application Processor (AP) can send crafted messages that trigger a buffer overflow inside the SCP firmware. Successful exploitation can compromise the confidentiality, integrity, and availability of the SCP, which manages power, clocks, and reset functions on Arm-based systems-on-chip.
Critical Impact
An Application Processor can trigger a buffer overflow in the SCP firmware, potentially leading to code execution or full compromise of the low-level system control processor.
Affected Products
- Arm SCP-Firmware version 2.11.0
- Arm SCP-Firmware versions 2.12.0 through 2.14.0
- Arm SCP-Firmware version 2.15.0
Discovery Timeline
- 2024-11-13 - CVE-2024-9413 published to NVD
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2024-9413
Vulnerability Analysis
The vulnerability resides in the transport_message_handler function, which processes messages exchanged between the Application Processor and the System Control Processor. The function fails to validate error conditions correctly before continuing message processing. When an unexpected error state occurs, execution proceeds with invalid assumptions about buffer sizes and message contents.
This leads to a buffer overflow condition in SCP firmware memory. Because the SCP is a privileged microcontroller responsible for platform power and security operations, memory corruption inside its firmware can undermine trust boundaries between the AP and lower-level system control.
Root Cause
The root cause is improper check for unusual or exceptional conditions [CWE-755] inside the transport_message_handler code path. The function does not correctly propagate or handle error return values from downstream operations. Downstream logic continues to operate on data as though the prior operation succeeded, resulting in writes that exceed allocated buffer boundaries.
Attack Vector
An attacker who controls code execution on the Application Processor can craft transport-layer messages that steer the SCP firmware into the vulnerable error path. The attack requires low privileges on the AP and some level of user interaction according to the CVSS vector. Because the SCP sits below the operating system trust boundary, a successful overflow can affect subsystems the AP itself is not authorized to touch. Refer to the Arm Security Center advisory for vendor-provided technical details.
No verified public proof-of-concept code is available for this vulnerability. See the vendor advisory for architectural context on the affected message transport path.
Detection Methods for CVE-2024-9413
Indicators of Compromise
- Unexpected SCP firmware crashes, resets, or watchdog timeouts on Arm-based platforms running SCP-Firmware 2.11.0 to 2.15.0.
- Anomalous transport-layer messages from the Application Processor that trigger error paths inside transport_message_handler.
- Platform instability, unexplained reboots, or power management anomalies coincident with AP-side workloads accessing SCP interfaces.
Detection Strategies
- Inventory firmware versions across Arm-based fleets and flag any system running SCP-Firmware 2.11.0 through 2.15.0.
- Correlate platform reset events and SCP crash telemetry with process activity on the Application Processor.
- Monitor build and supply chain artifacts to verify that shipped firmware images include the vendor-supplied fix.
Monitoring Recommendations
- Enable hardware and platform telemetry that surfaces SCP resets and firmware faults to a central logging pipeline.
- Ingest platform, kernel, and firmware logs into a centralized data lake for cross-source correlation and long-term retention.
- Track privileged process activity on the AP that interacts with SCP transport channels for later forensic review.
How to Mitigate CVE-2024-9413
Immediate Actions Required
- Identify all Arm-based systems running SCP-Firmware versions 2.11.0 through 2.15.0 and prioritize them for firmware updates.
- Apply the vendor-supplied fix from the Arm Security Center advisory as soon as it is qualified for the target platform.
- Restrict which processes on the Application Processor can send messages to the SCP transport interface.
Patch Information
Arm has published guidance in the Arm Security Center advisory for SCP-Firmware. Upgrade to a fixed release above 2.15.0 that includes the corrected error handling in transport_message_handler. Because SCP-Firmware is typically integrated by silicon vendors and OEMs, coordinate with the platform vendor to obtain a signed, qualified firmware image for deployment.
Workarounds
- Where feasible, reduce AP-side attack surface by limiting untrusted code execution on the Application Processor until firmware is updated.
- Enforce strict validation and rate limiting on higher-level software interfaces that expose SCP transport messaging to user workloads.
- Increase monitoring of SCP resets and firmware fault telemetry until patched firmware is deployed across the fleet.
# Example: verify SCP-Firmware version reported by the platform
# (exact command depends on the OEM/SoC vendor tooling)
fwupdmgr get-devices | grep -i scp
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
