Introduction
Remote attackers can take control of Samsung Galaxy devices by exploiting a flaw in the image processing pipeline. CVE-2025-21042 allows arbitrary code execution through a single malicious image file. It affects millions of users who rely on Samsung's proprietary image codec libraries.
Samsung Electronics is the largest smartphone manufacturer in the world, and its Galaxy series runs in both consumer and enterprise environments. The affected component, libimagecodec.quram.so, is a proprietary image processing library developed by Quramsoft. It has been deeply integrated into Samsung's Android stack since at least 2014. Earlier vulnerabilities in these libraries have had serious security consequences for the mobile ecosystem.
Technical Information
CVE-2025-21042 is an out-of-bounds write vulnerability in the libimagecodec.quram.so library, which parses and decodes a range of image formats on Samsung Galaxy devices. A specially crafted image file makes the library write outside the bounds of allocated memory.
The root cause is insufficient bounds checking during image parsing. When the library processes a malicious image, attacker-controlled data can overwrite adjacent memory regions. That memory corruption allows arbitrary code execution in the context of the image processing service or application.
The attack vector is fully remote. Any channel that gets the device to process an attacker-supplied image can deliver the exploit, including email attachments, messaging apps, and web browsing. The bug is particularly severe because system services and third-party apps often process images automatically, so exploitation needs minimal user interaction.
Earlier research into Samsung's Quram-based codecs (see CVE-2020-8899) found a pattern of memory safety issues, including buffer overflows and other forms of memory corruption. These issues come from insecure memory management in native code, especially where it handles untrusted input.
Affected Systems and Versions
- All Samsung Galaxy devices running firmware older than the April 2025 Security Maintenance Release (SMR Apr-2025 Release 1) are affected.
- The vulnerable component is
libimagecodec.quram.so. - Devices on the April 2025 SMR or later are not affected.
- Device configuration makes no difference, because the library handles image parsing system-wide.
Vendor Security History
- Samsung's proprietary image codecs from Quramsoft have had multiple memory safety vulnerabilities, including CVE-2020-8899 (buffer overflows in the Qmage codec).
- Samsung typically ships monthly Security Maintenance Releases to fix vulnerabilities, but public CVE assignment can lag behind patch deployment.
- Samsung collaborates with external researchers and has previously open-sourced fuzzing tools for testing image codecs.
