How CVE-2025-22066 Works
This vulnerability exists in the Linux kernel’s ASoC (ALSA System on Chip) subsystem, specifically in the `imx-card` driver. When `devm_kasprintf()` fails to allocate memory, it returns NULL, but the `imx_card_probe()` function does not validate this return value. This leads to a NULL pointer dereference when the kernel attempts to use the unallocated memory, potentially causing a kernel panic or local denial of service. The issue stems from improper error handling in the i.MX sound card driver initialization.
DailyCVE Form
Platform: Linux Kernel
Version: Up to 5.15.x
Vulnerability: NULL Dereference
Severity: Medium
Date: 05/06/2025
What Undercode Say:
Exploitation Analysis
- Triggerable via malicious sound card firmware
- Requires local access or crafted audio device
- Kernel panic leads to DoS
Protection Commands
Patch kernel to latest stable version sudo apt update && sudo apt upgrade linux-image-$(uname -r) Disable vulnerable driver (if unused) echo "blacklist snd-soc-imx-card" | sudo tee /etc/modprobe.d/imx-card.conf
Code Fix Example
// Original vulnerable code char str = devm_kasprintf(dev, GFP_KERNEL, "format"); use_str(str); // No NULL check // Patched code char str = devm_kasprintf(dev, GFP_KERNEL, "format"); if (!str) return -ENOMEM;
Detection Script
!/bin/bash if lsmod | grep -q "snd_soc_imx_card"; then echo "Vulnerable module loaded" else echo "System not vulnerable" fi
Kernel Config Hardening
CONFIG_DEBUG_KMEMLEAK=y CONFIG_DEBUG_SG=y CONFIG_DEBUG_LIST=y
Exploit PoC Concept
// Hypothetical local trigger
int main() {
system("echo malformed > /sys/class/sound/card0/firmware");
return 0;
}
Mitigation Summary
1. Update to kernel >= 5.15.123
2. Restrict physical device access
3. Enable kernel pointer protection
4. Monitor kernel oops logs
5. Apply grsecurity/PaX patches
Sources:
Reported By: nvd.nist.gov
Extra Source Hub:
Undercode
