CVE-2015-7892
📋 TL;DR
This vulnerability is a stack-based buffer overflow in Samsung's m2m1shot kernel driver framework. It allows local users to execute arbitrary code with kernel privileges by providing a large data.buf_out.num_planes value in an ioctl call. This affects Samsung S6 Edge devices running vulnerable kernel versions.
💻 Affected Systems
- Samsung Galaxy S6 Edge
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise with kernel-level code execution, allowing attackers to install persistent malware, bypass all security controls, and access all data on the device.
Likely Case
Local privilege escalation from a limited user to root/kernel privileges, enabling data theft, surveillance, or further system exploitation.
If Mitigated
Limited impact if SELinux or similar mandatory access controls are properly configured to restrict kernel module interactions.
🎯 Exploit Status
Exploit requires local access and knowledge of kernel memory layout. Public exploit code exists in exploit databases.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Samsung security patch (specific version not publicly documented in references)
Vendor Advisory: Not provided in references; check Samsung security advisories
Restart Required: Yes
Instructions:
1. Check for Samsung security updates in device settings. 2. Apply the latest security patch from Samsung. 3. Reboot the device to load the patched kernel.
🔧 Temporary Workarounds
Disable vulnerable ioctl
linuxRemove or restrict access to the vulnerable ioctl command in the m2m1shot driver
echo 0 > /proc/sys/kernel/m2m1shot_enabled (if such control exists)
chmod 000 /dev/m2m1shot (if device node exists)
SELinux enforcement
linuxConfigure SELinux to deny ioctl operations on the m2m1shot driver for untrusted applications
setenforce 1
Configure SELinux policies to restrict m2m1shot access
🧯 If You Can't Patch
- Restrict physical access to devices
- Implement application whitelisting to prevent untrusted apps from making ioctl calls
🔍 How to Verify
Check if Vulnerable:
Check kernel version and build date: uname -a. Look for Samsung S6 Edge with kernel build date before security patch.Check Version:
uname -aVerify Fix Applied:
Verify kernel version after update and check that security patch level is current in Settings > About phone.📡 Detection & Monitoring
Log Indicators:
- Kernel panic logs
- SELinux denials for m2m1shot ioctl operations
- Abnormal process spawning with root privileges
Network Indicators:
- None - local exploitation only
SIEM Query:
process:parent.name="*" AND process:name="su" OR process:name="sh" AND user:name="root" from non-standard parent🔗 References
- http://packetstormsecurity.com/files/134108/Samsung-M2m1shot-Kernel-Driver-Buffer-Overflow.html
- https://code.google.com/p/google-security-research/issues/detail?id=493
- https://www.exploit-db.com/exploits/38555/
- http://packetstormsecurity.com/files/134108/Samsung-M2m1shot-Kernel-Driver-Buffer-Overflow.html
- https://code.google.com/p/google-security-research/issues/detail?id=493
- https://www.exploit-db.com/exploits/38555/
