UBUNTU-CVE-2026-93818: Use After Free
In the Linux kernel, the following vulnerability has been resolved: PCI: plda: Protect root bus removal with rescan lock Hold the pcirescanremovelock lock while stopping and removing a root bus to avoid racing with concurrent rescan or hotplug operations triggered via sysfs. Such races may lead to use-after-free issues or system crashes. [bhelgaas: commit log]
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
ubuntu/linux-hwe-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-42.42~24.04.1 - Upgrade
Upgrade
ubuntu/linux-riscv-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-42.42.1~24.04.1 - Upgrade
Upgrade
ubuntu/linuxto a version that resolves this vulnerability.Fixed in 7.0.0-42.42 - Upgrade
Upgrade
ubuntu/linux-awsto a version that resolves this vulnerability.Fixed in 7.0.0-1016.17 - Upgrade
Upgrade
ubuntu/linux-gcpto a version that resolves this vulnerability.Fixed in 7.0.0-1016.18 - Upgrade
Upgrade
ubuntu/linux-ibmto a version that resolves this vulnerability.Fixed in 7.0.0-1017.17 - Upgrade
Upgrade
ubuntu/linux-oem-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-1017.17 - Upgrade
Upgrade
ubuntu/linux-oracleto a version that resolves this vulnerability.Fixed in 7.0.0-1015.16 - Upgrade
Upgrade
ubuntu/linux-riscvto a version that resolves this vulnerability.Fixed in 7.0.0-42.42.1 - Compensating control
Hold the pci_rescan_remove_lock while stopping and removing a PCI root bus to prevent races with concurrent sysfs-triggered rescan or hotplug operations.
Event History
Frequently Asked Questions
Which Ubuntu kernel package variants are listed as affected?
The listed software includes ubuntu/linux, ubuntu/linux-fips, ubuntu/linux-aws, ubuntu/linux-aws-fips, ubuntu/linux-azure, ubuntu/linux-azure-fips, ubuntu/linux-gcp, and ubuntu/linux-gcp-fips.
What conditions are needed for the described race to occur?
Root-bus stopping and removal must race with a concurrent PCI rescan or hotplug operation triggered through sysfs. The issue is associated with insufficient synchronization between those operations.