CVE-2022-48809
📋 TL;DR
This CVE describes a memory leak vulnerability in the Linux kernel's networking subsystem. When uncloning socket buffer (skb) destination metadata, an incorrect reference count leads to memory that is never freed. This affects all Linux systems using the vulnerable kernel versions.
💻 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 →⚠️ Risk & Real-World Impact
Worst Case
Sustained exploitation could lead to kernel memory exhaustion, causing system instability, denial of service, or potential kernel crashes.
Likely Case
Gradual memory consumption over time leading to performance degradation and eventual system instability or crashes under high network load.
If Mitigated
With proper monitoring and memory limits, impact is limited to performance degradation rather than complete system failure.
🎯 Exploit Status
Exploitation requires generating specific network conditions to trigger the uncloning behavior repeatedly.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Patches available in stable kernel branches (commits referenced in CVE)
Vendor Advisory: https://git.kernel.org/stable/c/00e6d6c3bc14dfe32824e2c515f0e0f2d6ecf2f1
Restart Required: Yes
Instructions:
1. Update Linux kernel to patched version from your distribution's repositories. 2. Reboot system to load new kernel.
🔧 Temporary Workarounds
Network traffic limiting
linuxReduce network traffic that triggers skb uncloning to slow memory leak
🧯 If You Can't Patch
- Implement aggressive memory monitoring and alerting for kernel memory usage
- Schedule regular system reboots to clear accumulated memory leaks
🔍 How to Verify
Check if Vulnerable:
Check kernel version against distribution's security advisories for affected versions
Check Version:
uname -r
Verify Fix Applied:
Verify kernel version matches patched version from distribution
📡 Detection & Monitoring
Log Indicators:
- Kernel oom-killer messages
- System memory exhaustion warnings
- Network subsystem errors
Network Indicators:
- Unusual network traffic patterns triggering skb operations
SIEM Query:
kernel: *oom* OR kernel: *memory* AND (panic OR error)
🔗 References
- https://git.kernel.org/stable/c/00e6d6c3bc14dfe32824e2c515f0e0f2d6ecf2f1
- https://git.kernel.org/stable/c/0be943916d781df2b652793bb2d3ae4f9624c10a
- https://git.kernel.org/stable/c/4ac84498fbe84a00e7aef185e2bb3e40ce71eca4
- https://git.kernel.org/stable/c/8b1087b998e273f07be13dcb5f3ca4c309c7f108
- https://git.kernel.org/stable/c/9eeabdf17fa0ab75381045c867c370f4cc75a613
- https://git.kernel.org/stable/c/a80817adc2a4c1ba26a7aa5f3ed886e4a18dff88
- https://git.kernel.org/stable/c/c1ff27d100e2670b03cbfddb9117e5f9fc672540
- https://git.kernel.org/stable/c/fdcb263fa5cda15b8cb24a641fa2718c47605314
- https://git.kernel.org/stable/c/00e6d6c3bc14dfe32824e2c515f0e0f2d6ecf2f1
- https://git.kernel.org/stable/c/0be943916d781df2b652793bb2d3ae4f9624c10a
- https://git.kernel.org/stable/c/4ac84498fbe84a00e7aef185e2bb3e40ce71eca4
- https://git.kernel.org/stable/c/8b1087b998e273f07be13dcb5f3ca4c309c7f108
- https://git.kernel.org/stable/c/9eeabdf17fa0ab75381045c867c370f4cc75a613
- https://git.kernel.org/stable/c/a80817adc2a4c1ba26a7aa5f3ed886e4a18dff88
- https://git.kernel.org/stable/c/c1ff27d100e2670b03cbfddb9117e5f9fc672540
- https://git.kernel.org/stable/c/fdcb263fa5cda15b8cb24a641fa2718c47605314