CVE-2025-58348: Samsung Exynos 980 Firmware DOS Vulnerability

CVE-2025-58348 Overview

A vulnerability has been discovered in the Wi-Fi driver used by Samsung Mobile and Wearable Processor Exynos chips. The flaw resides in the /proc/driver/unifi0/confg_tspec write operation handler, which fails to properly validate buffer size parameters before allocating kernel memory. This allows an attacker with local access to trigger unbounded memory allocation by specifying an excessively large buffer size, leading to kernel memory exhaustion and system denial of service.

Critical Impact

Local attackers can crash affected Samsung devices by exhausting kernel memory through malicious write operations to the Wi-Fi driver proc interface.

Affected Products

• Samsung Exynos 980, 850, 1080, 1280, 1330 Mobile Processors
• Samsung Exynos 1380, 1480, 1580 Mobile Processors
• Samsung Exynos W920, W930, W1000 Wearable Processors

Discovery Timeline

• 2026-02-03 - CVE-2025-58348 published to NVD
• 2026-02-05 - Last updated in NVD database

Technical Details for CVE-2025-58348

Vulnerability Analysis

This vulnerability is classified as CWE-770 (Allocation of Resources Without Limits or Throttling). The Wi-Fi driver component in Samsung Exynos processors exposes a proc filesystem interface at /proc/driver/unifi0/confg_tspec that allows configuration of traffic specification (TSPEC) parameters. When processing write operations to this interface, the driver allocates kernel memory based on user-supplied buffer size values without implementing proper bounds checking or resource limits.

The attack requires local access to the device, meaning an attacker would need either physical access or the ability to execute code on the device (such as through a malicious application). No authentication is required to interact with the vulnerable proc interface, and the attack does not require user interaction. While this vulnerability does not compromise confidentiality or integrity, the availability impact is high as successful exploitation results in complete system denial of service through kernel memory exhaustion.

Root Cause

The root cause of this vulnerability lies in improper input validation within the Wi-Fi driver's proc file write handler. The driver accepts user-controlled size parameters for buffer allocation without enforcing maximum limits or validating that the requested allocation size is reasonable for the intended TSPEC configuration operation. This violates secure coding principles that mandate bounds checking and resource throttling for any user-controllable memory allocation operations in kernel space.

Attack Vector

The attack vector is local, requiring the attacker to have execution capability on the affected device. The exploitation flow involves writing specially crafted data to the /proc/driver/unifi0/confg_tspec proc file with an oversized buffer length specification. When the driver processes this write request, it attempts to allocate the specified amount of kernel memory without validation. By repeatedly triggering large allocations or specifying an extremely large buffer size in a single operation, an attacker can exhaust available kernel memory, causing the system to become unresponsive or crash.

The attack is straightforward to execute once local access is achieved. A malicious application or script with sufficient permissions to write to the proc filesystem could trigger this condition. The vulnerability is particularly concerning for scenarios where untrusted code may execute on the device, such as through malicious apps or compromised system components.

Detection Methods for CVE-2025-58348

Indicators of Compromise

• Unusual memory consumption patterns in kernel space on affected Samsung Exynos devices
• System crashes or freezes coinciding with Wi-Fi driver activity
• Suspicious write operations to /proc/driver/unifi0/confg_tspec with abnormally large buffer sizes
• Kernel out-of-memory (OOM) killer activation without corresponding legitimate workload

Detection Strategies

• Monitor proc filesystem access patterns for writes to /proc/driver/unifi0/confg_tspec
• Implement kernel-level auditing for memory allocation requests exceeding normal operational thresholds
• Deploy endpoint detection solutions capable of monitoring low-level driver interactions on Android devices
• Review system logs for OOM conditions or kernel memory pressure events

Monitoring Recommendations

• Enable enhanced logging for Wi-Fi driver operations where supported by firmware
• Configure alerting for sudden kernel memory utilization spikes on mobile device fleets
• Utilize mobile device management (MDM) solutions to track device health and crash events across Samsung Exynos-based devices

How to Mitigate CVE-2025-58348

Immediate Actions Required

• Apply firmware updates from Samsung as soon as they become available for affected Exynos processors
• Restrict installation of untrusted applications that could potentially exploit this vulnerability
• Review and audit applications with elevated permissions on affected devices
• Consider isolating affected devices from sensitive environments until patches are applied

Patch Information

Samsung has published security advisories addressing this vulnerability. Affected users and organizations should monitor the Samsung Product Security Updates page and the specific CVE-2025-58348 advisory for firmware update availability and installation instructions. The patch is expected to implement proper bounds checking and resource limits for the confg_tspec write operation handler.

Workarounds

• Restrict physical access to affected devices to prevent local exploitation
• Enforce strict application installation policies through MDM to prevent malicious apps from reaching affected devices
• Disable or restrict access to the /proc/driver/unifi0/confg_tspec interface if operationally feasible (note: this may impact Wi-Fi functionality)
• Monitor device behavior for signs of exploitation attempts while awaiting official patches

# Check for affected Samsung Exynos processor (requires root access)
cat /proc/cpuinfo | grep -i exynos
# Monitor proc filesystem access (requires appropriate permissions)
cat /proc/filesystems | grep proc