CVE-2023-53504
📋 TL;DR
This CVE describes a use-after-free vulnerability in the Linux kernel's RDMA/bnxt_re driver. An attacker with local access could potentially exploit this to cause a kernel crash (denial of service) or execute arbitrary code. Systems using Broadcom NetXtreme-E RDMA adapters with affected kernel versions are vulnerable.
💻 Affected Systems
- Linux kernel with bnxt_re RDMA driver
📦 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 →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 →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 →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 →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 →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
Local privilege escalation to kernel-level code execution, potentially leading to complete system compromise.
Likely Case
Kernel panic or system crash causing denial of service.
If Mitigated
Limited to denial of service if exploit fails or system has additional protections like kernel address space layout randomization (KASLR).
🎯 Exploit Status
Exploitation requires local access and knowledge of kernel memory layout. No public exploits have been reported as of the knowledge cutoff.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Kernel versions with commit 5363fc488da579923edf6a2fdca3d3b651dd800b or c95863f6d970ef968e7c1f3c481f72a4b0734654
Vendor Advisory: https://git.kernel.org/stable/c/5363fc488da579923edf6a2fdca3d3b651dd800b
Restart Required: Yes
Instructions:
1. Update to a patched kernel version from your Linux distribution vendor. 2. Reboot the system to load the new kernel. 3. Verify the patch is applied by checking kernel version or commit hash.
🔧 Temporary Workarounds
Unload bnxt_re module
linuxRemove the vulnerable kernel module if RDMA functionality is not required
sudo rmmod bnxt_re
Blacklist bnxt_re module
linuxPrevent the module from loading at boot
echo 'blacklist bnxt_re' | sudo tee /etc/modprobe.d/blacklist-bnxt_re.conf
🧯 If You Can't Patch
- Restrict local user access to systems with vulnerable kernels
- Implement strict privilege separation and limit users who can load/unload kernel modules
🔍 How to Verify
Check if Vulnerable:
Check if bnxt_re module is loaded: lsmod | grep bnxt_re. If loaded, check kernel version against patched versions from your distribution.Check Version:
uname -rVerify Fix Applied:
Verify the kernel version includes the fix commit: grep -q '5363fc488da579923edf6a2fdca3d3b651dd800b\|c95863f6d970ef968e7c1f3c481f72a4b0734654' /proc/version || echo 'Check distribution patch notes'📡 Detection & Monitoring
Log Indicators:
- Kernel oops messages in /var/log/kern.log or dmesg
- System crashes or unexpected reboots
Network Indicators:
- None - this is a local vulnerability
SIEM Query:
EventID=41 OR Source='kernel' AND (Message LIKE '%Oops%' OR Message LIKE '%bnxt_re%')