CVE-2025-40034

Published Oct 28, 2025 Modified Apr 15, 2026

Description

In the Linux kernel, the following vulnerability has been resolved: PCI/AER: Avoid NULL pointer dereference in aer_ratelimit() When platform firmware supplies error information to the OS, e.g., via the ACPI APEI GHES mechanism, it may identify an error source device that doesn't advertise an AER Capability and therefore dev->aer_info, which contains AER stats and ratelimiting data, is NULL. pci_dev_aer_stats_incr() already checks dev->aer_info for NULL, but aer_ratelimit() did not, leading to NULL pointer dereferences like this one from the URL below: {1}[Hardware Error]: Hardware error from APEI Generic Hardware Error Source: 0 {1}[Hardware Error]: event severity: corrected {1}[Hardware Error]: device_id: 0000:00:00.0 {1}[Hardware Error]: vendor_id: 0x8086, device_id: 0x2020 {1}[Hardware Error]: aer_cor_status: 0x00001000, aer_cor_mask: 0x00002000 BUG: kernel NULL pointer dereference, address: 0000000000000264 RIP: 0010:___ratelimit+0xc/0x1b0 pci_print_aer+0x141/0x360 aer_recover_work_func+0xb5/0x130 [8086:2020] is an Intel "Sky Lake-E DMI3 Registers" device that claims to be a Root Port but does not advertise an AER Capability. Add a NULL check in aer_ratelimit() to avoid the NULL pointer dereference. Note that this also prevents ratelimiting these events from GHES. [bhelgaas: add crash details to commit log]

Is your site exposed to CVE-2025-40034?

Run a free security scan — no signup, results in seconds.

References

Frequently Asked Questions

What is CVE-2025-40034? +
In the Linux kernel, the following vulnerability has been resolved: PCI/AER: Avoid NULL pointer dereference in aer_ratelimit() When platform firmware supplies error information to the OS, e.g., via the ACPI APEI GHES mechanism, it may identify an error source device that doesn't advertise an AER Capability and therefore dev->aer_info, which contains AER stats and ratelimiting data, is NULL. pci_dev_aer_stats_incr() already checks dev->aer_info for NULL, but aer_ratelimit() did not, leading to NULL pointer dereferences like this one from the URL below: {1}[Hardware Error]: Hardware error from APEI Generic Hardware Error Source: 0 {1}[Hardware Error]: event severity: corrected {1}[Hardware Error]: device_id: 0000:00:00.0 {1}[Hardware Error]: vendor_id: 0x8086, device_id: 0x2020 {1}[Hardware Error]: aer_cor_status: 0x00001000, aer_cor_mask: 0x00002000 BUG: kernel NULL pointer dereference, address: 0000000000000264 RIP: 0010:___ratelimit+0xc/0x1b0 pci_print_aer+0x141/0x360 aer_recover_work_func+0xb5/0x130 [8086:2020] is an Intel "Sky Lake-E DMI3 Registers" device that claims to be a Root Port but does not advertise an AER Capability. Add a NULL check in aer_ratelimit() to avoid the NULL pointer dereference. Note that this also prevents ratelimiting these events from GHES. [bhelgaas: add crash details to commit log]
How do I check if I'm vulnerable to CVE-2025-40034? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Don't wait for an exploit

Scan your website for vulnerabilities like CVE-2025-40034 — free, no signup required.