CVE-2025-21454: Qualcomm Sa8620p Firmware DOS Vulnerability

CVE-2025-21454 Overview

CVE-2025-21454 is a transient denial of service (DoS) vulnerability affecting a wide range of Qualcomm chipsets and firmware. The vulnerability occurs during the processing of received beacon frames in wireless communication components. An attacker can exploit this flaw to cause a temporary service disruption by sending specially crafted beacon frames to affected devices over the network.

Critical Impact

This vulnerability enables network-based denial of service attacks against devices using affected Qualcomm chipsets, including mobile phones, automotive platforms, IoT devices, and wearables, potentially disrupting wireless connectivity without requiring authentication.

Affected Products

• Qualcomm Snapdragon 8 Gen 1/2/3 Mobile Platforms and Firmware
• Qualcomm Snapdragon 888/865/855 5G Mobile Platforms and Firmware
• Qualcomm FastConnect 6200/6700/6800/6900/7800 and Firmware
• Qualcomm SA8620P/SA8650P/SA8770P/SA8775P Automotive Platforms and Firmware
• Qualcomm Snapdragon X55/X65/X75 5G Modem-RF Systems and Firmware
• Qualcomm Robotics RB2/RB3/RB5 Platforms and Firmware
• Qualcomm Snapdragon XR1/XR2 5G Extended Reality Platforms and Firmware

Discovery Timeline

• July 8, 2025 - CVE-2025-21454 published to NVD
• August 11, 2025 - Last updated in NVD database

Technical Details for CVE-2025-21454

Vulnerability Analysis

This vulnerability is classified under CWE-126 (Buffer Over-read) and CWE-125 (Out-of-bounds Read). The flaw exists in the beacon frame processing logic within Qualcomm wireless firmware. When the affected component receives and processes a beacon frame, it fails to properly validate the boundaries of the data being read, leading to an out-of-bounds read condition.

The vulnerability can be exploited remotely over a network without requiring any privileges or user interaction. An attacker within wireless range can transmit malformed beacon frames that trigger the out-of-bounds read, causing the wireless subsystem to enter a transient denial of service state. While this does not allow for data exfiltration or code execution, it can effectively disrupt wireless connectivity for affected devices.

The impact is limited to availability, with no direct effect on confidentiality or integrity. The transient nature of the DoS means that service typically recovers after the attack stops, though repeated exploitation could cause sustained service disruption.

Root Cause

The root cause is improper input validation during beacon frame parsing. The firmware does not adequately verify the length and structure of incoming beacon frames before accessing their contents. This allows specially crafted frames with unexpected or malicious length fields to cause the parser to read beyond allocated buffer boundaries.

The out-of-bounds read occurs because the code trusts the length indicators in the beacon frame header without validating them against the actual buffer size. When these length values exceed the actual data present, the read operation accesses memory outside the intended bounds.

Attack Vector

The attack vector is network-based and requires the attacker to be within wireless communication range of the target device. The exploitation process involves:

1. The attacker crafts a malicious beacon frame with manipulated length fields or malformed information elements
2. The beacon frame is transmitted over the air to devices within range
3. Affected Qualcomm wireless firmware receives and attempts to parse the beacon frame
4. The parsing logic reads beyond buffer boundaries due to insufficient validation
5. The out-of-bounds read triggers a transient DoS condition in the wireless subsystem

No authentication is required to exploit this vulnerability, and no user interaction is needed. The attack can be performed by any entity within wireless range that can transmit beacon frames.

Detection Methods for CVE-2025-21454

Indicators of Compromise

• Unexpected wireless connectivity drops or instability on devices with Qualcomm chipsets
• Increased frequency of wireless subsystem crashes or restarts in device logs
• Detection of malformed or anomalous 802.11 beacon frames in wireless network captures
• Kernel or firmware crash logs indicating out-of-bounds read errors in WLAN components

Detection Strategies

• Deploy wireless intrusion detection systems (WIDS) to monitor for malformed beacon frames with suspicious length fields
• Implement firmware crash monitoring on devices to identify patterns consistent with beacon frame parsing failures
• Analyze wireless traffic captures for beacon frames with anomalous information element structures
• Monitor device health telemetry for wireless subsystem instability patterns

Monitoring Recommendations

• Enable detailed logging on wireless access points and controllers to capture beacon frame anomalies
• Implement continuous wireless spectrum monitoring in sensitive environments
• Configure alerting for patterns of wireless connectivity disruptions across multiple devices
• Review device crash dumps for signatures matching the vulnerability's exploitation pattern

How to Mitigate CVE-2025-21454

Immediate Actions Required

• Review the Qualcomm Security Bulletin July 2025 for affected product versions
• Prioritize firmware updates for devices in high-security or critical infrastructure environments
• Implement network segmentation to limit exposure of vulnerable wireless devices
• Consider temporary mitigations such as reducing wireless range or isolating affected devices where patching is delayed

Patch Information

Qualcomm has addressed this vulnerability in the July 2025 security bulletin. Organizations should obtain firmware updates through their device manufacturers or OEMs, as Qualcomm provides patches to device makers who then distribute updates through their respective channels.

The patch includes proper bounds checking during beacon frame parsing to prevent out-of-bounds read conditions. Administrators should consult the Qualcomm Security Bulletin July 2025 for specific patch identifiers and affected version details.

Workarounds

• Reduce wireless transmission power to limit the attack surface from distant adversaries
• Implement 802.11w (Protected Management Frames) where supported to provide some protection against frame injection attacks
• Deploy wireless intrusion prevention systems capable of detecting and blocking malformed beacon frames
• Consider wired connectivity alternatives for critical systems until firmware updates can be applied

# Example: Enable Protected Management Frames on Linux hostapd
# Add to /etc/hostapd/hostapd.conf
ieee80211w=2  # Required PMF for all clients