External risk intelligence

Hostapd and WPA Supplicant SAE Side Channel Vulnerability

CVE advisorySeverity: CRITICAL (CVSS 9.8)

CVE-2022-23303

This vulnerability affects hostapd and wpa_supplicant, which are used for local wireless network authentication and management. These components operate at the link layer within a physical or localized wireless range and are not designed for direct exposure to the public internet.

W1 Fi Hostapd

before 2.1035

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

A security vulnerability has been identified in widely used wireless network authentication software. This issue could potentially allow unauthorized access to sensitive information or disruption of network services by exploiting how the software handles data access patterns. The main concern is to confirm if these specific software components are in use within the organization.

Wireless security software has a flaw.
It enables unauthorized access to networks.
Confirm relevance and exposure.

Attack Path

How an attacker could exploit the issue

An attacker could exploit this vulnerability by sending specially crafted network traffic to a device running an affected version of hostapd or wpa_supplicant. This traffic, leveraging specific cache access patterns, could allow the attacker to infer sensitive information due to weaknesses in the SAE implementation.

No authentication or special privileges required.
Triggered by network traffic to vulnerable wireless authentication software.
Confidentiality, integrity, and availability risks.

Live Threat

Current exploitation, exposure, and threat context

When supported by the advisory, this vulnerability could allow an attacker to gain unauthorized access to sensitive information or disrupt wireless network services by exploiting weaknesses in how authentication data is handled. This could potentially affect the confidentiality and integrity of network communications.

Network authentication data could be at risk.
Side channel attacks may reveal sensitive information.
Unauthorized access to network services may occur.

Operational Fix

Recommended remediation, mitigation, and detection steps

This vulnerability impacts wireless network authentication software, likely managed by infrastructure or platform teams responsible for network services. The initial step is to identify all deployments, determine their business criticality and reachability, and then confirm the accountable owner before planning remediation.

Infrastructure teams should own the issue.
Verify system reachability and business criticality.
Plan remediation based on assessed risk.

Supplementary metadata

CVSS vector

Validate whether this threat affects your internet-facing exposure.

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Frequently asked questions

What is hostapd and wpa_supplicant?

These are core components for wireless networking on Linux systems. Hostapd allows a device to act as a wireless access point, while wpa_supplicant handles the client-side connection to Wi-Fi networks. They implement the protocols necessary to manage secure wireless authentication and association, forming the backbone for connectivity in many routers, IoT devices, and workstations.

How does CVE-2022-23303 work?

This vulnerability involves a side-channel attack targeting the Simultaneous Authentication of Equals (SAE) implementation. It falls under CWE-203, which relates to software that inadvertently reveals internal data through behavior. In this case, the way the software accesses system memory—specifically its cache patterns—can leak sensitive information during the authentication process, potentially allowing an attacker to deduce secret data.

What triggers this side-channel weakness?

The flaw is triggered by sending specifically crafted network traffic to an affected device during the SAE handshake. It is important to note that this is not triggered by standard, benign connection attempts or general network traffic; it specifically exploits the cryptographic processing behavior of the vulnerable SAE implementation.

Do I need to worry about internet exposure for this?

According to Halo Surface Signal, this vulnerability is considered very unlikely to be exposed to the public internet. Because hostapd and wpa_supplicant function at the link layer for local wireless management, they typically operate within a physical or localized range, making them fundamentally different from web applications designed for broad internet access.

When should I prioritize fixing this software?

Your first step is to perform an inventory to identify all systems running versions of hostapd or wpa_supplicant prior to 2.10. Prioritize remediation for devices that handle critical network services or operate in environments where unauthorized parties might gain wireless or local network proximity, then coordinate with infrastructure teams to update to the patched software versions.

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.