CVE-2022-48803
📋 TL;DR
This CVE describes an out-of-bounds read vulnerability in the Linux kernel's TI PHY driver (phy-j721e-wiz.c) where the clk_div_table array lacks a sentinel entry, causing KASAN to detect global-out-of-bounds memory access. This affects Linux systems using the Texas Instruments J721e hardware platform with vulnerable kernel versions. The vulnerability could lead to kernel crashes or potential information disclosure.
💻 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 →⚠️ Risk & Real-World Impact
Worst Case
Kernel panic leading to system crash, denial of service, or potential information disclosure from kernel memory.
Likely Case
System instability or kernel crash when the affected PHY driver initializes, particularly during boot or device probing.
If Mitigated
Minor performance impact or no effect if KASAN is disabled or the vulnerable code path isn't triggered.
🎯 Exploit Status
Exploitation requires triggering the specific code path during PHY initialization. The vulnerability was discovered through KASAN testing rather than real-world exploitation.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Fixed in kernel commits: 3c75d1017cb362b6a4e0935746ef5da28250919f, 5b0c9569135a37348c1267c81e8b0274b21a86ed, 6d1e6bcb31663ee83aaea1f171f3dbfe95dd4a69, 7a360e546ad9e7c3fd53d6bb60348c660cd28f54
Vendor Advisory: https://git.kernel.org/stable/c/3c75d1017cb362b6a4e0935746ef5da28250919f
Restart Required: Yes
Instructions:
1. Update to a kernel version containing the fix commits. 2. For distributions: Use package manager to update kernel package. 3. For custom kernels: Apply the git commits to your kernel source. 4. Reboot the system to load the new kernel.
🔧 Temporary Workarounds
Disable KASAN
linuxKernel Address Sanitizer detection can be disabled, though this doesn't fix the underlying vulnerability.
Rebuild kernel with CONFIG_KASAN=n
Blacklist affected driver
linuxPrevent loading of the vulnerable phy-j721e-wiz driver.
echo 'blacklist phy-j721e-wiz' >> /etc/modprobe.d/blacklist.conf
🧯 If You Can't Patch
- Ensure systems don't use Texas Instruments J721e hardware
- Implement strict access controls to prevent unauthorized local access
🔍 How to Verify
Check if Vulnerable:
Check kernel version and if phy-j721e-wiz module is loaded: lsmod | grep phy_j721e_wizCheck Version:
uname -rVerify Fix Applied:
Check kernel version contains fix commits or verify the driver loads without KASAN errors in dmesg📡 Detection & Monitoring
Log Indicators:
- KASAN error messages in kernel logs (dmesg) mentioning 'global-out-of-bounds' and 'clk_div_table'
- Kernel panic or crash during PHY initialization
Network Indicators:
- None - this is a local kernel vulnerability
SIEM Query:
source="kernel" AND ("KASAN" AND "global-out-of-bounds" AND "clk_div_table")🔗 References
- https://git.kernel.org/stable/c/3c75d1017cb362b6a4e0935746ef5da28250919f
- https://git.kernel.org/stable/c/5b0c9569135a37348c1267c81e8b0274b21a86ed
- https://git.kernel.org/stable/c/6d1e6bcb31663ee83aaea1f171f3dbfe95dd4a69
- https://git.kernel.org/stable/c/7a360e546ad9e7c3fd53d6bb60348c660cd28f54
- https://git.kernel.org/stable/c/3c75d1017cb362b6a4e0935746ef5da28250919f
- https://git.kernel.org/stable/c/5b0c9569135a37348c1267c81e8b0274b21a86ed
- https://git.kernel.org/stable/c/6d1e6bcb31663ee83aaea1f171f3dbfe95dd4a69
- https://git.kernel.org/stable/c/7a360e546ad9e7c3fd53d6bb60348c660cd28f54
