Summary 

At Pwn2Own Ireland 2025, researchers Ben R. and Georgi G. from Interrupt Labs successfully exploited a zero-day vulnerability in the Samsung Galaxy S25. The flaw allowed them to gain remote control of the device, activate the camera, and track the user’s real-time location without interaction.

This achievement, earning them $50,000 and 5 Master of Pwn points, highlighted ongoing security weaknesses even in flagship smartphones with extensive testing. The exploit’s discovery underlined broader concerns about the pace of Android feature development outstripping security hardening efforts across system and multimedia libraries. 

The Galaxy S25 zero-day exploit underscores the persistent threat of critical security flaws even in top-tier consumer devices. Although discovered in a controlled, ethical hacking event, such vulnerabilities pose substantial risks if leveraged by malicious actors.

Vulnerability Details 

The vulnerability originated from an improper input validation issue within the Galaxy S25’s software stack. Through carefully crafted malicious inputs, the researchers bypassed Samsung’s built-in security safeguards and executed arbitrary code remotely.

The exploit provided persistent access, enabling control over cameras, GPS, and potentially other sensitive device components, effectively transforming the smartphone into a covert surveillance tool. Because the issue existed at a deep system level, it required no user interaction, making it particularly severe. The vulnerability had not been previously disclosed, meaning Samsung and the public were both unaware until the competition’s revelation. 

Key characteristics: 

The key characteristics of the Samsung Galaxy S25 zero-day vulnerability are as follows: 

• Type of Vulnerability: Improper input validation bug within the device’s software stack, allowing remote code execution without user interaction.​ 

• Impact: Enables attackers to take full control of the device, activate the camera, and track real-time GPS location, effectively turning the device into a surveillance tool.​ 

• Discovery and Exploit: Uncovered during Pwn2Own Ireland 2025 by researchers Ben R. and Georgi G., showcasing a sophisticated exploit chain that bypassed Samsung’s security measures.​ 

• Persistence: Vulnerability allows persistent access, which can be exploited silently without user awareness or interaction.​ 

• Disclosure and Remediation: The flaw was previously undisclosed, with responsible disclosure leading to Samsung preparing a security patch. No official statement has been issued yet, but a fix is anticipated.​ 

• Severity and Potential Damage: The exploit can compromise sensitive personal data, private communications, and location, highlighting significant privacy and security risks. 

Attack Flow 

Proof-of-Concept 

The proof-of-concept for the Samsung Galaxy S25 zero-day vulnerability (CVE-2025-21043) demonstrates how specially crafted malicious images can exploit an out-of-bounds write flaw in Samsung’s closed-source image parsing library libimagecodec.quram.so. This flaw allows remote code execution with elevated privileges without requiring user interaction.

The exploit involves delivering a malicious payload embedded in an image file that, when processed by the vulnerable library, triggers memory corruption leading to arbitrary code execution and persistent control over the device.

This has been confirmed in cybersecurity forums and independent analyses, with active exploitation observed in the wild primarily via social engineering through messaging platforms like WhatsApp. The PoC confirms that attackers can bypass conventional security mechanisms and gain deep system control, enabling surveillance actions such as camera activation and location tracking. This underscores the critical need for applying the latest security patches released by Samsung.  

Source: https://x.com/thezdi/status/1981316237897396298 

Why It’s Effective 

• Code Execution via Input Validation Flaw: Exploits improper input validation within the Galaxy S25’s software stack, allowing malicious payloads to bypass safeguards and execute remote code seamlessly alongside legitimate system processes. 

• Zero-Click Capability: Operates without requiring any user interaction, enabling silent compromise through automated payloads that trigger upon data processing or system-level input handling. 

• Persistent Access: Establishes continuous control after initial compromise, granting long-term ability to activate hardware components like camera and GPS without detection by standard security mechanisms. 

• Stealth Operations: Exploit chain hides within multimedia and system library processes, avoiding visible alerts or performance anomalies that might indicate compromise to the user. 

• Advanced Evasion: Utilizes legitimate system libraries and resource calls, reducing the likelihood of being flagged by mobile antivirus or Samsung Knox runtime protections. 

• High Impact Vector: Enables complete device surveillance, capturing photos, videos, and location data covertly, illustrating real-world severity when attackers weaponize such system-level access. 

Remediation: 

• Update Samsung Galaxy devices immediately with the latest September 2025 Security Maintenance Release (SMR) patch that fixes CVE-2025-21043. 

• Manually check for software updates via Settings > Software Update > Download and Install to ensure the fix is applied promptly. 

• Enable automatic security updates on Samsung devices for timely future patching without delay. 

• For enterprises, enforce patch deployment policies through Mobile Device Management (MDM) or Enterprise Mobility Management (EMM) tools to cover all mobile endpoints. 

• Restrict app permissions, especially camera and location access, to minimize exposure in case of compromise. 

• Avoid opening images from untrusted sources or suspicious messaging apps, as the vulnerability exploits image parsing. 

• Implement continuous mobile threat detection to identify abnormal device behavior indicative of compromise. 

• Educate users and IT teams about the critical nature of this vulnerability and the importance of timely patching. 

This ensures comprehensive mitigation of vulnerability while reducing risk and exposure to active exploits. 

Conclusion: 

This incident reinforces the value of responsible disclosure mechanisms like Pwn2Own, where manufacturers receive detailed technical reports to develop patches before public release. Samsung has yet to issue a formal statement but is expected to roll out a security update imminently.

In the meantime, users are advised to enable automatic updates, remain cautious with app permissions and untrusted networks, and monitor official channels for patches to mitigate potential exploitation risks. 

References: 

• https://cybersecuritynews.com/samsung-galaxy-s25-0-day-vulnerability/ 

• https://cyberpress.org/samsung-galaxy-s25-0-day/ 

• https://gbhackers.com/hackers-exploit-galaxy-s25-0-day/amp/