CVE-2022-48998
📋 TL;DR
A stack corruption vulnerability in the Linux kernel's BPF JIT compiler for 32-bit PowerPC systems allows attackers to write beyond the stack boundary during tail call operations. This can lead to kernel crashes or potential privilege escalation. Systems running 32-bit PowerPC Linux kernels with BPF JIT enabled are affected.
💻 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 denial of service, or potential arbitrary code execution in kernel context resulting in full system compromise.
Likely Case
Kernel crash/panic causing system instability or denial of service when specific BPF programs with mismatched stack depths perform tail calls.
If Mitigated
No impact if BPF JIT is disabled or systems are not 32-bit PowerPC architecture.
🎯 Exploit Status
Exploitation requires ability to load BPF programs (typically requires CAP_BPF or root privileges) and specific knowledge of PowerPC architecture.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Linux kernel 6.1.0-rc4 and later, with backports to stable branches
Vendor Advisory: https://git.kernel.org/stable/c/747a6e547240baaaf41874d27333b87b87cfd24c
Restart Required: Yes
Instructions:
1. Update Linux kernel to version 6.1.0-rc4 or later
2. For older stable branches, apply commit 747a6e547240baaaf41874d27333b87b87cfd24c
3. Reboot system to load new kernel
🔧 Temporary Workarounds
Disable BPF JIT compiler
linuxDisable the BPF JIT compiler to prevent exploitation of this vulnerability
echo 0 > /proc/sys/net/core/bpf_jit_enable
Restrict BPF program loading
linuxLimit which users can load BPF programs using capabilities or SELinux/AppArmor
setcap -r /usr/bin/bpftool
chmod 750 /usr/bin/bpftool
🧯 If You Can't Patch
- Disable BPF JIT compiler via sysctl
- Implement strict access controls to prevent unauthorized users from loading BPF programs
🔍 How to Verify
Check if Vulnerable:
Check kernel version and architecture: uname -r should be < 6.1.0-rc4 and uname -m should show ppc or powerpc (32-bit)Check Version:
uname -rVerify Fix Applied:
Verify kernel version is 6.1.0-rc4 or later: uname -r📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages mentioning 'Unable to handle kernel data access'
- BPF-related crash logs
- System crashes during BPF program execution
SIEM Query:
event_type:"kernel_panic" AND message:"*Unable to handle kernel data access*" OR message:"*BPF*"