Summary
In the Linux kernel, the following vulnerability has been resolved: PCI/AER: Avoid NULL pointer...
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]
Impact
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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Frequently Asked Questions
- What is CVE-2025-40034? CVE-2025-40034 is a unknown-severity security vulnerability. No fixed version is listed yet.
- Is there a fix for CVE-2025-40034? No fixed version is listed for CVE-2025-40034 yet. Monitor the advisory for updates and apply mitigations in the interim.
- Is CVE-2025-40034 exploitable, and should I be worried? Whether CVE-2025-40034 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2025-40034 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.