CVE-2026-80732

CVE-2026-80732 is a use-after-free in the Linux kernel's pata_sl82c105 IDE/ATA driver. The driver looks up the SL82C105 PCI bridge with pci_get_slot(), which returns a referenced device, but a longstanding regression from commit 44c10138fd4b ('PCI: Change all drivers to use pci_device->revision') left the bridge's cached revision field being read after the reference was dropped with pci_dev_put(), so the device may already have been freed when its revision is accessed. The bug is exercised on the driver's PCI enumeration/initialization path on systems where this bridge is present, and a local attacker could potentially leverage the memory corruption for privilege escalation or a kernel crash (CVSS 7.8, local vector, no user interaction). Only Linux systems that build/load the pata_sl82c105 driver and have the legacy SL82C105 controller/bridge hardware are affected, which mostly means older or specialized x86 deployments. There is currently no known public proof-of-concept, the issue is not in the CISA KEV catalog, and EPSS puts 30-day exploitation probability at about 0.2%.

What to do: Update Linux kernels to builds that include the upstream fix, which reads the bridge revision before calling pci_dev_put(). Check exposure with 'lsmod' for the pata_sl82c105 module and 'lspci' for an SL82C105 controller; on systems without this legacy controller the flaw is unreachable, and blacklisting the module is a valid mitigation.