CVE-2024-43900
📋 TL;DR
A use-after-free vulnerability in the Linux kernel's xc2028 media driver allows attackers to potentially execute arbitrary code or cause system crashes. This affects Linux systems using the xc2028 tuner driver, particularly those with DVB hardware or media capture capabilities.
💻 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 →⚠️ Risk & Real-World Impact
Worst Case
Kernel memory corruption leading to arbitrary code execution with kernel privileges, system crashes, or privilege escalation.
Likely Case
System instability, kernel panics, or denial of service when the vulnerable driver is loaded and firmware loading fails.
If Mitigated
Minimal impact if systems don't use xc2028 tuner hardware or have the module blacklisted.
🎯 Exploit Status
Requires ability to trigger the firmware loading failure scenario and timing the use-after-free window. Likely requires local access.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Kernel versions with commits 208deb6d8c3cb8c3acb1f41eb31cf68ea08726d5, 68594cec291ff9523b9feb3f43fd853dcddd1f60, 850304152d367f104d21c77cfbcc05806504218b, or ef517bdfc01818419f7bd426969a0c86b14f3e0e
Vendor Advisory: https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html
Restart Required: Yes
Instructions:
1. Update Linux kernel to patched version from your distribution. 2. Reboot system to load new kernel. 3. Verify xc2028 module loads without errors.
🔧 Temporary Workarounds
Blacklist xc2028 module
linuxPrevent loading of vulnerable kernel module
echo 'blacklist xc2028' >> /etc/modprobe.d/blacklist-xc2028.conf
update-initramfs -u
reboot
Remove xc2028 firmware
linuxRemove firmware files to prevent driver initialization
rm -f /lib/firmware/dvb-fe-xc2028*
🧯 If You Can't Patch
- Blacklist xc2028 kernel module to prevent loading
- Restrict local user access to systems with vulnerable hardware
🔍 How to Verify
Check if Vulnerable:
Check if xc2028 module is loaded: lsmod | grep xc2028. If loaded and kernel version is unpatched, system is vulnerable.Check Version:
uname -rVerify Fix Applied:
Check kernel version includes fix commits or verify xc2028 module loads without triggering use-after-free in kernel logs.📡 Detection & Monitoring
Log Indicators:
- Kernel oops messages
- KASAN reports for use-after-free in load_firmware_cb
- xc2028 driver initialization failures
Network Indicators:
- None - local vulnerability
SIEM Query:
kernel: *BUG:* *KASAN:* *use-after-free* *load_firmware_cb* OR kernel: *xc2028* *firmware* *failed*🔗 References
- https://git.kernel.org/stable/c/208deb6d8c3cb8c3acb1f41eb31cf68ea08726d5
- https://git.kernel.org/stable/c/68594cec291ff9523b9feb3f43fd853dcddd1f60
- https://git.kernel.org/stable/c/850304152d367f104d21c77cfbcc05806504218b
- https://git.kernel.org/stable/c/ef517bdfc01818419f7bd426969a0c86b14f3e0e
- https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html
