CVE-2025-21042 Overview
CVE-2025-21042 is a critical out-of-bounds write vulnerability in Samsung's libimagecodec.quram.so library, a core image processing component used in Samsung Android devices. This vulnerability allows remote attackers to execute arbitrary code on affected devices without requiring any user interaction or authentication. The flaw exists in versions prior to the SMR Apr-2025 Release 1 security update.
Critical Impact
This vulnerability is actively being exploited in the wild and has been added to CISA's Known Exploited Vulnerabilities (KEV) catalog. Remote attackers can achieve full device compromise by exploiting the memory corruption flaw in the image codec library, potentially gaining complete control over affected Samsung devices.
Affected Products
- Samsung Android 13.0 (all SMR releases prior to Apr-2025 Release 1)
- Samsung Android 14.0 (all SMR releases prior to Apr-2025 Release 1)
- Samsung Android 15.0 (versions prior to Apr-2025 Release 1)
Discovery Timeline
- September 12, 2025 - CVE CVE-2025-21042 published to NVD
- November 12, 2025 - Last updated in NVD database
Technical Details for CVE-2025-21042
Vulnerability Analysis
The vulnerability resides in libimagecodec.quram.so, Samsung's proprietary image codec library developed by Quram. This shared library handles image decoding and encoding operations on Samsung Android devices. The out-of-bounds write condition (CWE-787) occurs during image processing operations, where improper boundary validation allows an attacker to write data beyond the allocated memory buffer.
According to Palo Alto Unit 42's analysis, this vulnerability has been associated with commercial-grade Android spyware campaigns. The exploitation requires no privileges and can be triggered remotely over the network without user interaction, making it particularly dangerous for mobile device security.
The network-accessible nature of this vulnerability combined with the lack of required authentication creates a scenario where attackers can target devices simply by sending a malicious image to the victim. When the image is processed by the vulnerable codec library, the out-of-bounds write is triggered, leading to memory corruption that can be leveraged for code execution.
Root Cause
The root cause is insufficient bounds checking in the image decoding routines within libimagecodec.quram.so. When processing specially crafted image data, the library fails to properly validate the size and boundaries of input data before writing to memory buffers. This allows attackers to write arbitrary data beyond the intended buffer boundaries, corrupting adjacent memory regions and enabling control flow hijacking.
Attack Vector
The attack vector for CVE-2025-21042 is network-based remote exploitation. An attacker can craft a malicious image file containing specially designed payload data and deliver it to a target device through various channels such as messaging applications, email, web browsing, or MMS. When the vulnerable libimagecodec.quram.so library attempts to process the malicious image, the out-of-bounds write is triggered. The attacker can leverage this memory corruption to achieve arbitrary code execution with the privileges of the process handling the image, potentially gaining persistent access to the device.
Detection Methods for CVE-2025-21042
Indicators of Compromise
- Unusual process crashes or restarts in media processing services on Samsung devices
- Unexpected network connections originating from image processing or gallery applications
- Presence of unknown or suspicious files created after image viewing activities
- Anomalous memory usage patterns in processes utilizing libimagecodec.quram.so
Detection Strategies
- Monitor for abnormal crashes in media-related processes such as the gallery app or messaging services
- Implement Mobile Device Management (MDM) solutions to verify Samsung Security Maintenance Release (SMR) patch levels
- Deploy mobile threat detection solutions capable of identifying exploitation attempts against image codec libraries
- Analyze network traffic for suspicious image file downloads from untrusted sources
Monitoring Recommendations
- Enable detailed logging on MDM platforms to track device patch compliance
- Configure alerts for devices running Samsung Android versions prior to SMR Apr-2025 Release 1
- Monitor for indicators associated with the Landfall spyware campaign as documented by Unit 42
- Implement SentinelOne Mobile Threat Defense to detect and prevent exploitation attempts on enterprise mobile devices
How to Mitigate CVE-2025-21042
Immediate Actions Required
- Apply the Samsung Security Maintenance Release (SMR) Apr-2025 Release 1 update immediately on all affected devices
- For organizations with unpatched devices, consider restricting MMS and automatic image downloading until patches can be applied
- Isolate devices that cannot be immediately patched from sensitive network resources
- Verify patch deployment through MDM reporting and compliance dashboards
Patch Information
Samsung has addressed this vulnerability in the SMR Apr-2025 Release 1 security update. The patch is available through the Samsung Security Update Portal. Organizations should ensure all Samsung Android 13.0, 14.0, and 15.0 devices are updated to at least the April 2025 SMR release. Due to the active exploitation of this vulnerability and its inclusion in CISA's Known Exploited Vulnerabilities catalog, federal agencies and critical infrastructure organizations have mandatory patching timelines.
Workarounds
- Disable automatic image downloading in messaging applications and email clients
- Configure devices to block MMS auto-retrieval until the patch is applied
- Use enterprise Mobile Threat Defense solutions like SentinelOne to provide runtime protection
- Restrict access to untrusted image sources through network filtering and web security policies
# Verify Samsung Android security patch level via ADB
adb shell getprop ro.build.version.security_patch
# Expected output for patched devices: 2025-04-01 or later
# Check for vulnerable library presence
adb shell ls -la /system/lib64/libimagecodec.quram.so
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
