CVE-2022-49250
📋 TL;DR
This CVE describes an out-of-bounds memory access vulnerability in the Linux kernel's ASoC (Audio System on Chip) codec driver for rx-macro. The flaw occurs when the kernel incorrectly attempts to access compander data for AUX interpolator, which doesn't exist, potentially leading to kernel memory corruption. This affects Linux systems using the affected ASoC codec drivers.
💻 Affected Systems
- Linux kernel with ASoC rx-macro codec 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 →⚠️ Risk & Real-World Impact
Worst Case
Kernel panic, system crash, or potential privilege escalation if an attacker can trigger the out-of-bounds access to manipulate kernel memory.
Likely Case
System instability, audio subsystem malfunctions, or denial of service through kernel crashes.
If Mitigated
Limited impact with proper kernel hardening and memory protection features enabled.
🎯 Exploit Status
Exploitation requires triggering specific audio codec operations. No public exploits known as of analysis.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Linux kernel versions containing the fix commits: 42c709c4e1ce4c136891530646c9abd5dff3524f, 6aa8ef9535dbd561293406608ebe791627b10196, 87a2b44cb3005d30c3a72234d1e47b03ae3bb29a, 9208ecc703b5ed5b12d7ea13c79207f4c8456638
Vendor Advisory: https://git.kernel.org/stable/c/42c709c4e1ce4c136891530646c9abd5dff3524f
Restart Required: No
Instructions:
1. Update Linux kernel to version containing the fix commits. 2. For embedded systems: update kernel through vendor firmware updates. 3. For distributions: apply security updates from your distribution's repository.
🔧 Temporary Workarounds
Disable affected audio driver
allBlacklist or disable the rx-macro ASoC driver if not needed
echo 'blacklist snd-soc-rx-macro' >> /etc/modprobe.d/blacklist.conf
rmmod snd_soc_rx_macro
🧯 If You Can't Patch
- Restrict audio device access to trusted users only
- Implement kernel hardening features like KASLR and memory protection
🔍 How to Verify
Check if Vulnerable:
Check if rx-macro driver is loaded: lsmod | grep rx_macro. Check kernel version against patched versions.Check Version:
uname -rVerify Fix Applied:
Verify kernel version includes fix commits. Check that audio functionality works without crashes.📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages
- Audio subsystem crashes in dmesg
- Out-of-bounds access warnings in kernel logs
Network Indicators:
- None - this is a local kernel vulnerability
SIEM Query:
Search for: 'kernel panic', 'BUG:', 'general protection fault' in system logs when audio operations occur