CVE-2026-43200 PCI: endpoint: Fix swapped parameters in pci_{primary/secondary}_epc_epf_unlink() functions
A parameter swap in Linux kernel PCI endpoint unlink functions causes a kernel crash, leading to denial of service.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-43200?
CVE-2026-43200 is a medium-severity vulnerability in Linux kernel, published on 6 May 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
PCI: endpoint: Fix swapped parameters in pci_{primary/secondary}_epc_epf_unlink() functions
struct configfs_item_operations callbacks are defined like the following:
int (*allow_link)(struct config_item *src, struct config_item *target); void (*drop_link)(struct config_item *src, struct config_item *target);
While pci_primary_epc_epf_link() and pci_secondary_epc_epf_link() specify the parameters in the correct order, pci_primary_epc_epf_unlink() and pci_secondary_epc_epf_unlink() specify the parameters in the wrong order, leading to the below kernel crash when using the unlink command in configfs:
Unable to handle kernel paging request at virtual address 0000000300000857 Mem abort info: ... pc : string+0x54/0x14c lr : vsnprintf+0x280/0x6e8 ... string+0x54/0x14c vsnprintf+0x280/0x6e8 vprintk_default+0x38/0x4c vprintk+0xc4/0xe0 pci_epf_unbind+0xdc/0x108 configfs_unlink+0xe0/0x208+0x44/0x74 vfs_unlink+0x120/0x29c __arm64_sys_unlinkat+0x3c/0x90 invoke_syscall+0x48/0x134 do_el0_svc+0x1c/0x30prop.0+0xd0/0xf0
[mani: cced stable, changed commit message as per https://lore.kernel.org/linux-pci/aV9joi3jF1R6ca02@ryzen]
Which versions are affected by CVE-2026-43200?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-43200?
Apply the vendor's patch.
Is CVE-2026-43200 being exploited?
There is no known exploitation of CVE-2026-43200 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2026-43200, DEBIAN-CVE-2026-43200, GHSA-h3wc-x575-rqjq, ROOT-OS-UBUNTU-2204-CVE-2026-43200, ROOT-OS-UBUNTU-2404-CVE-2026-43200, UBUNTU-CVE-2026-43200.