CVE-2025-57835: Samsung Exynos 990 Firmware DOS Vulnerability

CVE-2025-57835 Overview

A critical improper memory initialization vulnerability has been identified in the Radio Resource Control (RRC) component of Samsung Exynos Mobile Processors, Wearable Processors, and Modems. This vulnerability allows remote attackers to cause a system crash by sending a malformed RRCReconfiguration message, resulting in an illegal memory access condition. The flaw affects a wide range of Samsung Exynos chipsets used in smartphones, wearables, and standalone modems.

Critical Impact

Remote attackers can trigger a complete system crash on affected Samsung Exynos-powered devices by exploiting improper memory initialization in the RRC protocol handler, causing denial of service without requiring 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-2025-57835 published to NVD
• April 7, 2026 - Last updated in NVD database

Technical Details for CVE-2025-57835

Vulnerability Analysis

This vulnerability resides in the RRC (Radio Resource Control) layer of Samsung Exynos baseband firmware. The RRC protocol is responsible for establishing, configuring, and releasing radio bearers in LTE and 5G networks. When processing RRCReconfiguration messages, the affected firmware fails to properly initialize memory structures before accessing them, leading to an illegal memory access condition.

The vulnerability is classified under CWE-20 (Improper Input Validation), as the RRC handler does not adequately validate the structure and content of incoming RRCReconfiguration messages before processing them. This allows specially crafted malformed messages to trigger uninitialized memory access, resulting in a denial of service condition.

Root Cause

The root cause stems from improper memory initialization within the RRC message parsing routines in Samsung Exynos baseband firmware. When the RRC layer receives an RRCReconfiguration message, certain memory structures are accessed before being properly initialized. If a malformed message triggers a specific code path, the uninitialized memory contains unpredictable values that cause the processor to access invalid memory addresses, resulting in a system crash.

Attack Vector

The attack can be executed remotely over the cellular network without requiring any authentication or user interaction. An attacker with the capability to transmit cellular signals (such as through a rogue base station or compromised cellular infrastructure) can craft and send malicious RRCReconfiguration messages to target devices. The attack exploits the implicit trust relationship between cellular devices and base stations during the RRC connection reconfiguration process.

The exploitation process involves constructing a malformed RRCReconfiguration message with specific field values or structure anomalies that trigger the uninitialized memory access path. When the vulnerable Exynos baseband processor receives and attempts to parse this message, the improper memory initialization causes an illegal memory access, leading to immediate system crash and denial of service.

Detection Methods for CVE-2025-57835

Indicators of Compromise

• Unexpected device reboots or crashes, particularly during cellular connectivity
• Abnormal baseband processor behavior or modem crashes
• Multiple instances of system crashes occurring in areas with potentially rogue cellular infrastructure
• Device logs showing RRC-related errors immediately before system crashes

Detection Strategies

• Monitor device crash logs for patterns indicating RRC protocol processing failures
• Implement cellular network anomaly detection to identify malicious base station activity
• Deploy MDM (Mobile Device Management) solutions to track and correlate device crash events across enterprise fleets
• Analyze baseband crash dumps for signatures of uninitialized memory access in RRC handlers

Monitoring Recommendations

• Enable detailed logging on mobile device management platforms to capture crash reports
• Monitor for geographic clustering of device crashes that may indicate a rogue base station attack
• Implement network-based detection for anomalous RRC message patterns at the carrier level
• Track firmware versions across device fleets to identify unpatched vulnerable devices

How to Mitigate CVE-2025-57835

Immediate Actions Required

• Apply the latest Samsung firmware updates for affected Exynos-powered devices as soon as available
• Prioritize patching for devices used in high-security environments or by personnel in sensitive positions
• Consider temporary operational restrictions in environments where rogue base station attacks are a credible threat
• Inventory all devices containing affected Samsung Exynos processors to scope the vulnerability impact

Patch Information

Samsung has released security updates addressing this vulnerability. Detailed patch information is available through the Samsung Semiconductor Security Updates portal and the CVE-2025-57835 specific advisory. Device manufacturers using Samsung Exynos chipsets should integrate the patched baseband firmware into their device updates.

Organizations should coordinate with their device vendors (Samsung, Google, Vivo, etc.) to determine when patches will be available for specific device models. For enterprise deployments, prioritize testing and deployment of firmware updates through MDM infrastructure.

Workarounds

• No complete workarounds are available as the vulnerability exists at the baseband firmware level
• Avoid using affected devices in areas where rogue base station attacks are suspected until patches are applied
• For enterprise environments, consider enhanced physical security measures to reduce the risk of proximity-based attacks
• Implement device monitoring to quickly identify and respond to crash events that may indicate exploitation attempts

# Check device firmware version on Android devices
adb shell getprop ro.build.version.baseband
# Compare the output against Samsung's security bulletin to verify patch status
# Enterprise MDM commands will vary by platform (Intune, Jamf, etc.)