CVE-2024-56556
📋 TL;DR
A race condition in the Linux kernel's binder subsystem allows use-after-free of binder nodes, potentially leading to kernel memory corruption. This affects Linux systems using the Android binder IPC mechanism. Attackers with local access could exploit this to crash the system or potentially escalate privileges.
💻 Affected Systems
- Linux kernel
📦 What is this software?
Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →⚠️ Risk & Real-World Impact
Worst Case
Kernel memory corruption leading to system crash (DoS) or potential privilege escalation to root.
Likely Case
System crash or instability due to kernel memory corruption.
If Mitigated
No impact if patched or binder subsystem not in use.
🎯 Exploit Status
Exploitation requires local access and race condition triggering. The KASAN report shows the bug can be triggered via binder_ioctl.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Linux kernel versions containing fixes 38fbefeb2c140b581ed7de8117a5c90d6dd89c22 or dc8aea47b928cc153b591b3558829ce42f685074
Vendor Advisory: https://git.kernel.org/stable/c/38fbefeb2c140b581ed7de8117a5c90d6dd89c22
Restart Required: Yes
Instructions:
1. Update Linux kernel to version containing the fix. 2. Reboot system to load new kernel. 3. For Android devices, wait for vendor security update.
🔧 Temporary Workarounds
Disable binder subsystem
linuxRemove binder kernel module if not required (breaks Android compatibility)
rmmod binder
echo 'blacklist binder' >> /etc/modprobe.d/blacklist.conf
🧯 If You Can't Patch
- Restrict local user access to systems
- Implement strict SELinux/AppArmor policies to limit binder access
🔍 How to Verify
Check if Vulnerable:
Check kernel version and if binder is loaded: 'uname -r' and 'lsmod | grep binder'Check Version:
uname -rVerify Fix Applied:
Verify kernel version is updated and check dmesg for absence of binder-related KASAN errors📡 Detection & Monitoring
Log Indicators:
- KASAN reports in dmesg/kernel logs about binder UAF
- System crashes or instability related to binder
Network Indicators:
- None - local exploit only
SIEM Query:
kernel: *KASAN* AND *binder* AND *use-after-free*