CVE-2023-53640
📋 TL;DR
This CVE describes a use-after-free vulnerability in the Linux kernel's ASoC (Audio System on Chip) lpass driver that allows reading kernel memory out of bounds. Attackers with local access could potentially leak sensitive kernel memory or cause system instability. This affects Linux systems with Qualcomm audio hardware using the vulnerable driver.
💻 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 →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 memory disclosure leading to privilege escalation, system crash, or information leakage of sensitive kernel data structures.
Likely Case
Local information disclosure of kernel memory, potential system instability or crashes when accessing audio controls.
If Mitigated
Minimal impact with proper access controls and kernel hardening features like KASAN enabled.
🎯 Exploit Status
Exploitation requires local access and specific audio hardware. The vulnerability was discovered through syzkaller fuzzing.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Patches available in stable kernel trees (commits: 75e5fab7db0cecb6e16b22c34608f0b40a4c7cd1, 8d81d3b0ed3610d24191d24f8e9e20f6775f0cc5, 8f1512d78b5de928f4616a871e77b58fd546e651, f5e61e3fe799ba2fda4320af23d26d28c3302045)
Vendor Advisory: https://git.kernel.org/stable/c/75e5fab7db0cecb6e16b22c34608f0b40a4c7cd1
Restart Required: Yes
Instructions:
1. Update to a patched kernel version from your distribution vendor. 2. Apply the specific kernel patches if building custom kernel. 3. Reboot the system to load the new kernel.
🔧 Temporary Workarounds
Disable vulnerable driver module
linuxPrevent loading of the vulnerable lpass driver if not required
echo 'blacklist snd_soc_lpass' > /etc/modprobe.d/blacklist-lpass.conf
rmmod snd_soc_lpass
🧯 If You Can't Patch
- Restrict local user access to systems with vulnerable hardware
- Enable kernel hardening features like KASAN to detect exploitation attempts
🔍 How to Verify
Check if Vulnerable:
Check if lpass driver is loaded: lsmod | grep lpass. Check kernel version against patched versions.Check Version:
uname -rVerify Fix Applied:
Verify kernel version is updated and lpass driver version includes the fix commits.📡 Detection & Monitoring
Log Indicators:
- KASAN reports of 'slab-out-of-bounds' or 'use-after-free' in kernel logs
- Audio subsystem crashes or errors
Network Indicators:
- None - local vulnerability only
SIEM Query:
kernel: *KASAN* AND (*slab-out-of-bounds* OR *use-after-free*) AND *regcache_flat_read*