CVE-2025-21042 Overview
CVE-2025-21042 is an out-of-bounds write vulnerability in libimagecodec.quram.so, the Quramsoft image parsing library bundled with Samsung Android devices. The flaw allows remote attackers to execute arbitrary code on affected handsets by delivering a malicious image, with no user interaction required. Samsung addressed the issue in the SMR Apr-2025 Release 1 security maintenance update. The vulnerability is tracked under [CWE-787] (Out-of-bounds Write) and has been added to the CISA Known Exploited Vulnerabilities catalog. Palo Alto Networks Unit 42 has linked exploitation of this flaw to the LANDFALL commercial-grade Android spyware operation targeting Samsung Galaxy devices.
Critical Impact
Remote attackers can achieve arbitrary code execution on unpatched Samsung Android devices by sending a crafted image, enabling full device compromise and deployment of commercial spyware.
Affected Products
- Samsung Android 13.0 prior to SMR Apr-2025 Release 1
- Samsung Android 14.0 prior to SMR Apr-2025 Release 1
- Samsung Android 15.0 prior to SMR Apr-2025 Release 1
Discovery Timeline
- 2025-09-12 - CVE-2025-21042 published to NVD
- 2025-11-12 - Last updated in NVD database
Technical Details for CVE-2025-21042
Vulnerability Analysis
The vulnerability exists in libimagecodec.quram.so, a closed-source image decoding library developed by Quramsoft and shipped on Samsung Android devices. The library processes image formats during parsing operations performed by system components and messaging applications. When the library handles a malformed image, it writes data beyond the bounds of an allocated buffer, corrupting adjacent memory.
Attackers can leverage this memory corruption to overwrite control structures and redirect execution flow. Because the parsing routines run within privileged media-handling contexts, successful exploitation yields arbitrary code execution on the device. Unit 42 reports that this primitive has been used to deploy LANDFALL, a commercial-grade Android spyware family targeting Galaxy users.
Root Cause
The root cause is improper bounds validation during image format parsing within the Quramsoft codec. The library fails to verify that calculated offsets or lengths from image metadata remain within the bounds of the destination buffer before performing write operations, resulting in an out-of-bounds write classified as [CWE-787].
Attack Vector
Exploitation is achievable over the network with no privileges and no user interaction. An attacker delivers a crafted image to the target device through messaging services, email, or other channels that trigger automatic image processing by Samsung system components. Parsing the malicious file triggers the out-of-bounds write and grants the attacker code execution within the media processing context.
No public proof-of-concept code is available. The vulnerability mechanism is described in the Palo Alto Networks Unit 42 LANDFALL spyware analysis.
Detection Methods for CVE-2025-21042
Indicators of Compromise
- Unexpected processes spawned by media or messaging applications immediately after image receipt, particularly child processes of system media services.
- Crashes or repeated restarts of components linked to libimagecodec.quram.so recorded in device logs.
- Outbound connections from mobile devices to infrastructure associated with LANDFALL spyware as documented in the Unit 42 analysis.
- Presence of unsigned or unknown native libraries persisting in application data directories on Samsung Galaxy devices.
Detection Strategies
- Hunt for anomalous DEX or native code loaded by messaging and gallery applications using mobile threat defense telemetry.
- Correlate inbound image deliveries with subsequent crashes in media parsing components to surface exploitation attempts.
- Apply known LANDFALL network and file IOCs published by Unit 42 to mobile EDR and network monitoring tooling.
Monitoring Recommendations
- Track Samsung security patch level (SPL) across the mobile fleet and flag devices below SMR Apr-2025 Release 1.
- Monitor DNS and TLS metadata from mobile networks for connections to LANDFALL command-and-control infrastructure.
- Enable mobile threat defense capabilities that inspect native library behavior on Android endpoints.
How to Mitigate CVE-2025-21042
Immediate Actions Required
- Install the Samsung SMR Apr-2025 Release 1 security maintenance update or any later monthly SMR on all Galaxy devices running Android 13, 14, or 15.
- Prioritize patching for executives, journalists, and other targets historically focused on by commercial spyware vendors.
- Audit messaging applications and disable automatic image download where feasible until devices are confirmed patched.
Patch Information
Samsung released the fix in SMR Apr-2025 Release 1. Patch availability and rollout details are documented in the Samsung Mobile Security Update bulletin. Carriers and OEM partners distribute the update through standard over-the-air channels. Confirm the installed Android security patch level reflects April 2025 or later.
Workarounds
- Disable auto-download of media in messaging applications such as Samsung Messages, WhatsApp, and Signal until the patch is applied.
- Restrict receipt of MMS and rich media from unknown senders through carrier or MDM policy.
- Reboot devices regularly to disrupt non-persistent implants while patches are being deployed.
# Verify Samsung Android security patch level via ADB
adb shell getprop ro.build.version.security_patch
# Expected output for remediated devices: 2025-04-01 or later
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
