CVE-2025-54324 Overview
A denial of service vulnerability has been discovered in the Non-Access Stratum (NAS) component of Samsung Exynos mobile processors, wearable processors, and modems. The vulnerability stems from incorrect handling of Downlink (DL) NAS Transport packets, which can be exploited remotely over the network to cause a denial of service condition on affected devices.
Critical Impact
Remote attackers can exploit this vulnerability to disrupt cellular connectivity on millions of Samsung Galaxy devices, wearables, and devices using Exynos modems without requiring any authentication or user interaction.
Affected Products
- Samsung Exynos Mobile Processors: 980, 990, 850, 1080, 2100, 1280, 2200, 1330, 1380, 1480, 2400, 1580, 2500
- Samsung Exynos Wearable Processors: 9110, W920, W930, W1000
- Samsung Exynos Modems: 5123, 5300, 5400
Discovery Timeline
- April 6, 2026 - CVE-2025-54324 published to NVD
- April 7, 2026 - Last updated in NVD database
Technical Details for CVE-2025-54324
Vulnerability Analysis
This vulnerability resides in the NAS (Non-Access Stratum) protocol handling layer of Samsung Exynos baseband firmware. The NAS protocol operates at the control plane of 4G LTE and 5G networks, responsible for managing mobility, session handling, and security procedures between the mobile device (User Equipment) and the core network.
The flaw specifically affects how the baseband processor handles DL NAS Transport messages. These messages are used to carry SMS-over-NAS, location services data, and other NAS signaling between the network and the device. When a malformed DL NAS Transport packet is received, the baseband firmware fails to properly validate or handle the packet structure, leading to resource exhaustion and service disruption.
The vulnerability is classified under CWE-400 (Uncontrolled Resource Consumption), indicating that the improper packet handling leads to excessive resource usage that ultimately causes the denial of service condition. The attack requires network access but no privileges or user interaction, making it exploitable by any attacker who can inject packets into the cellular network path.
Root Cause
The root cause is improper input validation in the NAS message processing routine of the Exynos baseband firmware. When processing DL NAS Transport packets, the firmware does not adequately verify message boundaries, length fields, or container contents before attempting to process them. This allows specially crafted packets to trigger resource exhaustion or processing errors that crash or hang the baseband processor, severing cellular connectivity.
Attack Vector
The attack can be executed remotely over the cellular network. An attacker with the capability to inject or relay crafted NAS signaling messages—potentially through a rogue base station, compromised network infrastructure, or man-in-the-middle position on the radio link—can send malicious DL NAS Transport packets to vulnerable devices.
Due to the nature of NAS protocol processing occurring at the baseband level before most application-layer protections, traditional mobile security software cannot intercept or block these attacks. The victim's device would experience sudden loss of cellular connectivity, potentially requiring a device restart to recover.
Detection Methods for CVE-2025-54324
Indicators of Compromise
- Unexpected loss of cellular connectivity on Samsung devices with Exynos processors
- Baseband crash logs or modem restart events in device diagnostic data
- Repeated NAS protocol errors visible in network signaling traces
- Unusual patterns of DL NAS Transport messages in cellular network logs
Detection Strategies
- Monitor Mobile Device Management (MDM) systems for sudden cellular disconnection events across Samsung Exynos-based device fleets
- Implement network-level analysis at cellular core infrastructure to detect malformed NAS Transport messages
- Review baseband firmware crash dumps on affected devices for NAS-related exceptions
- Deploy anomaly detection for unusual NAS signaling patterns in carrier network monitoring systems
Monitoring Recommendations
- Enable diagnostic logging on Samsung devices to capture baseband events and crash reports
- Configure alerting in enterprise MDM platforms for widespread cellular connectivity loss
- Coordinate with mobile carriers to monitor for suspicious NAS signaling activity
- Track firmware update status across device fleet to ensure patched versions are deployed
How to Mitigate CVE-2025-54324
Immediate Actions Required
- Apply Samsung firmware updates as soon as they become available for affected Exynos processors
- Monitor Samsung's security bulletin page for patch availability for specific device models
- Prioritize updates for devices in high-security or mission-critical deployments
- Consider temporary use of Wi-Fi connectivity for critical communications while awaiting patches
Patch Information
Samsung has acknowledged this vulnerability and released security updates. Detailed patch information is available through Samsung's official semiconductor security resources:
Organizations should check with their device vendors (Samsung Mobile, other OEMs using Exynos chips) for specific firmware update timelines and availability.
Workarounds
- No complete workaround exists since the vulnerability is in baseband firmware processing
- Limit exposure by avoiding untrusted cellular network connections where possible
- Use VoWiFi (Voice over Wi-Fi) and Wi-Fi-based connectivity as an alternative when in high-risk environments
- Enterprise environments should implement MDM policies to enforce prompt firmware updates
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
