CVE-2025-47202: Samsung Exynos Buffer Overflow Flaw

CVE-2025-47202 Overview

CVE-2025-47202 is a critical out-of-bounds write vulnerability affecting the Radio Resource Control (RRC) component in Samsung Mobile Processors, Wearable Processors, and Modems across the Exynos product line. The vulnerability stems from a missing length check in the RRC layer, which can allow attackers to write data beyond allocated memory boundaries. This flaw impacts a wide range of Samsung semiconductor products used in smartphones, wearables, and standalone modem implementations.

Critical Impact

Network-accessible out-of-bounds write vulnerability in baseband firmware affecting millions of devices across Samsung's Exynos processor and modem lineup, potentially enabling remote code execution or denial of service without user interaction.

Affected Products

• Samsung Exynos Mobile Processors (980, 990, 850, 1080, 2100, 1280, 2200, 1330, 1380, 1480, 2400, 1580)
• Samsung Exynos Wearable Processors (9110, W920, W930, W1000)
• Samsung Exynos Modems (5123, 5300, 5400)

Discovery Timeline

• 2025-07-07 - CVE-2025-47202 published to NVD
• 2025-10-27 - Last updated in NVD database

Technical Details for CVE-2025-47202

Vulnerability Analysis

This vulnerability resides in the RRC (Radio Resource Control) layer of Samsung's baseband firmware. RRC is a critical component of the cellular protocol stack responsible for managing radio connection establishment, maintenance, and release between user equipment and the cellular network. The flaw allows attackers to potentially compromise device integrity and availability through network-based attack vectors without requiring any user interaction or special privileges.

The out-of-bounds write condition (CWE-787) occurs due to insufficient validation of length parameters when processing RRC messages. When malformed or crafted RRC signaling data is received, the vulnerable code fails to properly verify that write operations stay within allocated buffer boundaries, resulting in memory corruption.

Root Cause

The root cause of CVE-2025-47202 is the absence of proper length validation checks in the RRC message parsing routines within the Exynos baseband firmware. When the firmware processes incoming RRC protocol data units (PDUs), it does not adequately verify that the length fields contained within these messages correspond to the actual allocated buffer sizes. This oversight allows an attacker who can inject or manipulate RRC messages to specify length values that cause the firmware to write data past the end of designated memory regions.

Attack Vector

The attack vector for this vulnerability is network-based, meaning exploitation can occur remotely over cellular network connections. An attacker positioned as a rogue base station or capable of performing a man-in-the-middle attack on cellular communications could craft malicious RRC messages targeting vulnerable devices. The attack requires no authentication or user interaction, as RRC messaging occurs at the baseband level before higher-layer security mechanisms come into play.

Potential attack scenarios include:

• Setting up a malicious cellular base station that broadcasts crafted RRC messages
• Intercepting and modifying legitimate RRC traffic between a device and legitimate base station
• Exploiting the vulnerability to cause denial of service by crashing the baseband processor
• Potentially achieving arbitrary code execution within the baseband context

Detection Methods for CVE-2025-47202

Indicators of Compromise

• Unexpected baseband crashes or modem restarts without apparent cause
• Abnormal cellular connection behavior including frequent disconnections or connection failures
• Device instability specifically related to cellular functionality
• Unusual network activity patterns from devices with affected Exynos processors

Detection Strategies

• Monitor device logs for baseband processor exceptions or crash dumps
• Implement network-level monitoring to detect anomalous RRC signaling patterns
• Deploy endpoint detection solutions capable of monitoring baseband health status
• Analyze cellular network traffic for malformed RRC protocol messages

Monitoring Recommendations

• Enable comprehensive logging on mobile device management (MDM) platforms to track baseband health
• Establish baseline behavior patterns for cellular connectivity to identify deviations
• Monitor for vendor security bulletins and ensure timely firmware update deployment
• Consider implementing cellular network anomaly detection for enterprise environments

How to Mitigate CVE-2025-47202

Immediate Actions Required

• Review the Samsung Product Security Updates page for available patches
• Apply firmware updates as soon as they become available from Samsung or device manufacturers
• Inventory all devices containing affected Exynos processors or modems within the organization
• Prioritize updates for devices handling sensitive communications

Patch Information

Samsung has published a security advisory for this vulnerability. Organizations and users should refer to the Samsung CVE-2025-47202 Advisory for detailed patch information and firmware update availability. Firmware updates are typically distributed through device manufacturers (OEMs) that integrate Samsung Exynos processors into their products, so users should check with their specific device vendor for update availability.

Workarounds

• There are no known software workarounds for this baseband-level vulnerability
• In high-security environments, consider restricting devices to Wi-Fi-only connectivity until patches are applied
• Avoid connecting affected devices to untrusted or unknown cellular networks
• Monitor Samsung's security portal for updated mitigation guidance