CVE-2024-44983
📋 TL;DR
A vulnerability in the Linux kernel's netfilter flowtable component allows uninitialized memory access when processing VLAN headers. This could lead to kernel memory corruption, crashes, or potential privilege escalation. All Linux systems using affected kernel versions with netfilter flowtable enabled are vulnerable.
💻 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 →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 leading to system crash, or potential privilege escalation to kernel mode allowing complete system compromise.
Likely Case
System instability, kernel crashes, or denial of service affecting network connectivity.
If Mitigated
Limited impact if flowtable is disabled or systems are not processing VLAN traffic.
🎯 Exploit Status
Exploitation requires sending specially crafted VLAN packets to trigger the uninitialized memory access. No public exploit code is known at this time.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Multiple stable kernel versions with fixes available (see git commit references in CVE)
Vendor Advisory: https://git.kernel.org/stable/c/0279c35d242d037abeb73d60d06a6d1bb7f672d9
Restart Required: Yes
Instructions:
1. Update Linux kernel to patched version from your distribution's repositories. 2. Reboot system to load new kernel. 3. Verify kernel version after reboot.
🔧 Temporary Workarounds
Disable netfilter flowtable
linuxDisable the vulnerable flowtable feature to prevent exploitation
echo 0 > /proc/sys/net/netfilter/nf_flowtable_offload
sysctl -w net.netfilter.nf_flowtable_offload=0
Block VLAN traffic
linuxUse firewall rules to block VLAN-tagged traffic if not required
iptables -A INPUT -m vlan --vlan-tag 1-4094 -j DROP
iptables -A FORWARD -m vlan --vlan-tag 1-4094 -j DROP
🧯 If You Can't Patch
- Disable netfilter flowtable feature using sysctl commands
- Implement network segmentation to limit VLAN traffic to trusted sources only
🔍 How to Verify
Check if Vulnerable:
Check if flowtable is enabled: cat /proc/sys/net/netfilter/nf_flowtable_offload. If returns 1 and kernel version is unpatched, system is vulnerable.Check Version:
uname -rVerify Fix Applied:
Check kernel version after update matches patched version from distribution. Verify flowtable can be safely enabled.📡 Detection & Monitoring
Log Indicators:
- Kernel panic logs
- System crash dumps
- Network interface errors
Network Indicators:
- Unusual VLAN traffic patterns
- Malformed VLAN packets
SIEM Query:
source="kernel" AND ("Kernel panic" OR "BUG" OR "uninit-value" OR "flowtable")🔗 References
- https://git.kernel.org/stable/c/0279c35d242d037abeb73d60d06a6d1bb7f672d9
- https://git.kernel.org/stable/c/043a18bb6cf16adaa2f8642acfde6e8956a9caaa
- https://git.kernel.org/stable/c/6ea14ccb60c8ab829349979b22b58a941ec4a3ee
- https://git.kernel.org/stable/c/c05155cc455785916164aa5e1b4605a2ae946537
- https://git.kernel.org/stable/c/d9384ae7aec46036d248d1c2c2757e471ab486c3
- https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html
