Listen to this Post
How the Mentioned CVE Works
The vulnerability stems from a hardware defect in older VIA Technologies VT6415 and VT6330 PATA host controllers. When these specific chipsets attempt to perform Direct Memory Access (DMA) operations with attached ATAPI devices (such as optical CD/DVD drives), a flaw in the controller’s logic can cause a complete system lockup. The system experiences a “hard hang” without generating debug traces or crash logs, making diagnosis difficult. This can be triggered by standard operations like reading disc information (e.g., using the `cdrecord -atip` command). In some configurations with certain optical drives, the hang can occur during system boot, preventing startup entirely. The bug is specific to DMA transactions with ATAPI devices; hard disk drives (HDDs) using the same controller are not affected. The Linux kernel’s `pata_via` driver previously allowed DMA mode for these devices on the buggy controllers. The fix forces these combinations to use the slower but reliable Programmed Input/Output (PIO) mode instead.
dailycve form
Platform: Linux Kernel
Version: Multiple versions
Vulnerability: Denial of Service
Severity: Medium
date: 2025-07-10
Prediction: 2025-09-08
What Undercode Say:
Bash Commands and Codes:
Command to trigger the vulnerability (may cause system hang) cdrecord -vvv -atip /dev/sr0 Check kernel version uname -r Verify if the pata_via module is loaded lsmod | grep pata_via Check system logs for related warnings dmesg | grep -i "ata|pata_via"
// Code snippet from the fix in drivers/ata/pata_via.c
if (dev->class == ATA_DEV_ATAPI &&
(dmi_check_system(no_atapi_dma_dmi_table) ||
config->id == PCI_DEVICE_ID_VIA_6415)) {
ata_dev_warn(dev, "controller locks up on ATAPI DMA, forcing PIO\n");
mask &= ATA_MASK_PIO;
}
How Exploit:
An attacker with local access could exploit this flaw by triggering DMA operations on a connected ATAPI device (e.g., a DVD drive), causing a persistent denial-of-service by hanging the system. Physical access to connect a malicious or specific optical drive is a potential vector.
Protection from this CVE
Apply kernel update containing commit d29fc02caad7f94b62d56ee1b01c954f9c961ba7. For unpatched systems, avoid using ATAPI devices on VT6415/VT6330 controllers.
Impact:
System hard hang. Prevents system booting. Requires physical restart.
🎯Let’s Practice Exploiting & Learn Patching For Free:
Sources:
Reported By: nvd.nist.gov
Extra Source Hub:
Undercode
