CVE-2022-49001
📋 TL;DR
This CVE describes a race condition vulnerability in the RISC-V Linux kernel's virtual memory stack overflow handling. When multiple processor cores (harts) simultaneously experience stack overflows, they can corrupt the shared shadow stack used for recovery, potentially leading to kernel crashes or privilege escalation. This affects systems running Linux kernels with RISC-V architecture support.
💻 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 →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 conditions when multiple cores experience stack overflows simultaneously.
If Mitigated
Minor performance impact from the atomic locking mechanism, with no security impact when patched.
🎯 Exploit Status
Exploitation requires triggering stack overflows on multiple harts simultaneously, which is difficult to achieve reliably.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Kernel versions containing the fix commits (7e1864332fbc1b993659eab7974da9fe8bf8c128, 879fabc5a95401d9bce357e4b1d24ae4a360a81f, ac00301adb19df54f2eae1efc4bad7447c0156ce)
Vendor Advisory: https://git.kernel.org/stable/c/7e1864332fbc1b993659eab7974da9fe8bf8c128
Restart Required: Yes
Instructions:
1. Update Linux kernel to version containing the fix commits. 2. For distributions: Use package manager to update kernel package. 3. Reboot system to load new kernel.
🔧 Temporary Workarounds
Disable vmap stack feature
linuxDisable virtual memory mapping for kernel stacks to avoid the vulnerable code path
Add 'nokaslr' or specific RISC-V kernel parameters to disable vmap stack feature (distribution specific)
🧯 If You Can't Patch
- Restrict local user access to prevent potential exploitation
- Implement strict resource limits to prevent stack overflow conditions
🔍 How to Verify
Check if Vulnerable:
Check kernel version and if RISC-V architecture is used. Examine kernel configuration for vmap stack support.Check Version:
uname -rVerify Fix Applied:
Verify kernel version includes the fix commits. Check that spin_shadow_stack atomic variable implementation is present in kernel source.📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages
- Stack overflow warnings in kernel logs
- Multiple concurrent stack overflow events
Network Indicators:
- None - this is a local vulnerability
SIEM Query:
Search for kernel panic events or stack overflow warnings in system logs on RISC-V systems