External risk intelligence

Linux Kernel iwlwifi Driver NUL Termination Vulnerability

CVE advisorySeverity: CRITICAL (CVSS 9.1)

CVE-2024-35845

This vulnerability affects a specific Linux kernel driver (iwlwifi) responsible for handling Wi-Fi hardware debug information. It is not a network-exposed service, API, or application interface. It requires local access to the hardware or execution context to trigger, and it is not reachable from the public internet in typical deployments.

Linux Kernel

5.5 to before 5.10.2145.11 to before 5.15.1535.16 to before 6.1.836.2 to before 6.6.236.7 to before 6.7.116.8 to before 6.8.210.0

Halo Surface Signal: 1 out of 5 — much less likely to be public-facing.

External exposure likelihood

Horizon Alert

Summary of the vulnerability and why it matters

This Linux kernel vulnerability involves how debug information is handled in the Wi-Fi driver, specifically ensuring string termination. While resolved, understanding its nature is important for verifying if related systems are impacted.

Fixes a Wi-Fi driver issue with debug string handling.
Confirm relevance and exposure for affected Linux systems.
Focus on verifying if your Linux kernel is impacted.

Attack Path

How an attacker could exploit the issue

An attacker could leverage this vulnerability by interacting with the Wi-Fi debugging features of the Linux kernel. This might involve sending specially crafted debug data that is not properly terminated, leading to unexpected behavior within the iwlwifi driver. If successful, this could allow an attacker to cause a system crash or potentially execute arbitrary code.

Triggered by malformed debug data.
Affects Wi-Fi driver debugging.
Potential for crashes or code execution.

Live Threat

Current exploitation, exposure, and threat context

The Linux kernel's Wi-Fi driver could be affected when processing debug information, potentially leading to unintended system behavior.

Wi-Fi debug data could be corrupted.
Malformed debug data could be processed.
System instability or unexpected behavior may occur.

Operational Fix

Recommended remediation, mitigation, and detection steps

This vulnerability in the Linux kernel's Wi-Fi driver necessitates that infrastructure and platform teams collaborate to identify affected systems, particularly those handling wireless debug data. The first practical step is to confirm the presence and reachability of the vulnerable driver component, assess its business criticality, and then engage the accountable system owner to plan a coordinated remediation, considering the potential impact on wireless functionality.

Infrastructure and platform teams own remediation.
Verify driver presence and wireless network exposure.
Plan coordinated updates during maintenance windows.

Supplementary metadata

CVSS vector

Validate whether this threat affects your internet-facing exposure.

Halo Threat Intelligence helps prioritize remediation with Halo Surface Signal and H/A/L/O context. Start exposure validation with a free external attack surface trial.

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Frequently asked questions

What is the Linux kernel iwlwifi driver?

The iwlwifi driver is a component within the Linux kernel that manages Wi-Fi hardware functionality for Intel wireless adapters. It allows the operating system to communicate with the network card to handle connectivity tasks. The driver also includes specific debugging features, known as debug-TLV, which are designed to capture and process technical information about wireless device performance and status for troubleshooting purposes.

What is the security weakness in CVE-2024-35845?

This issue is classified under CWE-134, which generally relates to improper input handling. Specifically, the iwlwifi driver failed to properly ensure that debug information strings were NUL-terminated. Because these strings are processed as character sequences, a missing termination character can cause the software to continue reading past the intended data buffer, leading to memory-related errors that may result in system instability or crashes.

How can an attacker trigger this vulnerability?

An attacker needs to provide malformed or specially crafted debug data to the iwlwifi driver's processing routines. Simply using a standard Wi-Fi connection for internet access does not trigger this flaw. The vulnerability requires interaction with the driver's specific internal debugging interfaces, meaning typical network traffic or normal wireless usage is insufficient to initiate the error state.

Is my system at risk according to Halo Surface Signal?

Halo Surface Signal notes that this vulnerability is very unlikely to be exploited from the public internet. The flaw is localized to a specific driver component rather than an exposed network service or public-facing API. Because it requires a local execution context or hardware-level interaction, systems are not generally accessible to remote attackers in typical server or desktop deployments.

What steps should I take if I use Linux?

Start by identifying if your Linux kernel version falls within the ranges listed as affected in the catalog. You should then coordinate with your infrastructure team to plan a kernel update during a standard maintenance window. Prioritize systems that are most critical to your operations or those where you have policies in place to maintain current, patched kernel versions for all hardware-level drivers.

References

Written by Nicholas Merritt

Nicholas Merritt is VP of Security Solutions at Halo Security. With more than 25 years across application security, vulnerability prioritization, and offensive security, he helps teams translate threat data into practical exposure validation and remediation focus. He authors Halo Threat Intelligence CVE advisories using Halo Surface Signal and H/A/L/O context to prioritize internet-facing risk.