CVE-2023-53213
📋 TL;DR
This CVE describes a slab-out-of-bounds read vulnerability in the Linux kernel's brcmfmac WiFi driver. An attacker could trigger this by sending specially crafted association request frames, potentially leading to kernel memory corruption. Systems using Broadcom WiFi chips with the affected driver are vulnerable.
💻 Affected Systems
- Linux kernel with brcmfmac 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 →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
Kernel panic leading to denial of service, or potential arbitrary code execution in kernel context resulting in full system compromise.
Likely Case
Kernel crash causing system instability or denial of service, requiring reboot to recover.
If Mitigated
System remains stable with proper input validation preventing buffer overflow.
🎯 Exploit Status
Found via syzkaller fuzzing. Exploitation requires sending malicious WiFi association frames to trigger the vulnerable code path.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Patched in kernel commits: 0da40e018fd0, 21bee3e649d8, 228186629ea9, 39f9bd880aba, 425eea395f1f
Vendor Advisory: https://git.kernel.org/stable/c/0da40e018fd034d87c9460123fa7f897b69fdee7
Restart Required: Yes
Instructions:
1. Update Linux kernel to version containing fixes. 2. For distributions: Use package manager (apt/yum/dnf) to update kernel. 3. Reboot system to load new kernel.
🔧 Temporary Workarounds
Disable vulnerable WiFi interface
linuxTemporarily disable WiFi interfaces using brcmfmac driver
sudo ip link set wlan0 down
sudo rfkill block wifi
Use alternative WiFi driver
linuxSwitch to different WiFi chip/driver if available
🧯 If You Can't Patch
- Implement network segmentation to isolate WiFi networks from critical systems
- Use WiFi security controls to restrict association to trusted devices only
🔍 How to Verify
Check if Vulnerable:
Check kernel version and if brcmfmac module is loaded: lsmod | grep brcmfmac && uname -rCheck Version:
uname -rVerify Fix Applied:
Verify kernel version is updated and check dmesg for absence of brcmfmac-related crashes📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages
- KASAN reports for brcmfmac
- Out-of-bounds read errors in dmesg
Network Indicators:
- Unusual WiFi association patterns
- Malformed 802.11 association frames
SIEM Query:
source="kernel" AND ("brcmfmac" OR "KASAN" OR "slab-out-of-bounds")🔗 References
- https://git.kernel.org/stable/c/0da40e018fd034d87c9460123fa7f897b69fdee7
- https://git.kernel.org/stable/c/21bee3e649d87f78fe8aef6ae02edd3d6f310fd0
- https://git.kernel.org/stable/c/228186629ea970cc78b7d7d5f593f2d32fddf9f6
- https://git.kernel.org/stable/c/39f9bd880abac6068bedb24a4e16e7bd26bf92da
- https://git.kernel.org/stable/c/425eea395f1f5ae349fb55f7fe51d833a5324bfe
- https://git.kernel.org/stable/c/549825602e3e6449927ca1ea1a08fd89868439df
- https://git.kernel.org/stable/c/936a23293bbb3332bdf4cdb9c1496e80cb0bc2c8
- https://git.kernel.org/stable/c/ac5305e5d227b9af3aae25fa83380d3ff0225b73
- https://git.kernel.org/stable/c/e29661611e6e71027159a3140e818ef3b99f32dd
