CVE-2023-53607
📋 TL;DR
This CVE-2023-53607 is a Linux kernel vulnerability in the YMFPCI sound card driver where a BUG_ON assertion triggers a kernel warning during device probe. The issue occurs when the driver incorrectly checks buffer alignment size, causing a kernel warning that could potentially lead to system instability. This affects Linux systems with YMFPCI sound hardware or the snd_ymfpci module loaded.
💻 Affected Systems
- Linux kernel
⚠️ Risk & Real-World Impact
Worst Case
Kernel panic or system crash if the BUG_ON triggers in production, leading to denial of service and potential data loss.
Likely Case
Kernel warning in dmesg during device initialization, possibly causing sound card initialization failure but system remains operational.
If Mitigated
Minor system log noise with no functional impact if the warning is handled gracefully.
🎯 Exploit Status
This is a local driver initialization bug, not a security vulnerability that can be actively exploited. The CVSS score reflects potential denial of service impact.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Fixed in kernel commits: 32b9bd7cfc2e2d92d595386add4e111b232b351f, 6be2e7522eb529b41c16d459f33bbdbcddbf5c15, 81d2a7e93c8322ca6b858f6736d7fc3d034e6c23, 96e34c88000febc83e41aa7db0b0a41676314818, d0217b09910c081b6471181345ea5b24025edf51
Vendor Advisory: https://git.kernel.org/stable/c/32b9bd7cfc2e2d92d595386add4e111b232b351f
Restart Required: Yes
Instructions:
1. Update Linux kernel to version containing the fix. 2. For distributions: Use package manager (apt/yum/dnf) to update kernel. 3. Reboot system to load new kernel.
🔧 Temporary Workarounds
Blacklist snd_ymfpci module
linuxPrevent loading of the vulnerable driver module
echo 'blacklist snd_ymfpci' >> /etc/modprobe.d/blacklist-ymfpci.conf
update-initramfs -u
reboot
Disable YMFPCI hardware
linuxDisable the sound card in BIOS/UEFI if not needed
🧯 If You Can't Patch
- Ensure YMFPCI hardware is not present in the system
- Monitor kernel logs for BUG_ON warnings and have reboot procedures ready
🔍 How to Verify
Check if Vulnerable:
Check if snd_ymfpci module is loaded: lsmod | grep snd_ymfpci. Check kernel version against patched versions.Check Version:
uname -rVerify Fix Applied:
After update, check kernel version and ensure no BUG_ON warnings appear in dmesg during boot.📡 Detection & Monitoring
Log Indicators:
- Kernel warnings containing 'snd_ymfpci' and 'BUG_ON' in /var/log/kern.log or dmesg output
Network Indicators:
- None - this is a local driver issue
SIEM Query:
source="kernel" AND "snd_ymfpci" AND "BUG_ON"🔗 References
- https://git.kernel.org/stable/c/32b9bd7cfc2e2d92d595386add4e111b232b351f
- https://git.kernel.org/stable/c/6be2e7522eb529b41c16d459f33bbdbcddbf5c15
- https://git.kernel.org/stable/c/81d2a7e93c8322ca6b858f6736d7fc3d034e6c23
- https://git.kernel.org/stable/c/96e34c88000febc83e41aa7db0b0a41676314818
- https://git.kernel.org/stable/c/d0217b09910c081b6471181345ea5b24025edf51
