CVE-2024-50040 is a vulnerability in the Linux kernel's igb network driver, which manages Intel Gigabit Ethernet adapters. The flaw arises from improper handling of non-fatal PCIe errors during device error recovery. Specifically, the igb_io_error_detected() function was modified to ignore non-fatal PCIe errors to prevent hung tasks caused by multiple calls to igb_down(). However, this change led to a logic inconsistency where igb_io_resume(), which assumes the device was brought down if the interface is up, attempts to bring the device back up even when igb_io_error_detected() did not bring it down. This mismatch causes a kernel panic due to an invalid opcode triggered in napi_enable(), resulting in a system crash. The stack trace shows the panic occurs during PCIe Advanced Error Reporting (AER) handling when a non-fatal but uncorrectable PCIe transaction layer error is detected. The root cause is that igb_io_resume() does not verify if the device was actually brought down before attempting to bring it up, leading to a kernel BUG at net/core/dev.c. The fix ensures igb_io_resume() checks both if the interface is running and the device is not down before proceeding, preventing the panic. This vulnerability affects Linux kernel versions containing the specified commits prior to the fix. Exploitation requires triggering specific PCIe non-fatal errors on affected Intel igb network devices, which could be induced by hardware faults or potentially malicious PCIe transactions. While no known exploits are reported in the wild, the vulnerability can cause denial of service via system crashes on affected systems using the igb driver for Intel Gigabit Ethernet adapters.

For European organizations, this vulnerability poses a risk primarily to servers and network infrastructure running Linux with Intel igb network adapters. The impact is a denial of service condition caused by kernel panics, which can disrupt critical network services, data center operations, and enterprise applications relying on stable network connectivity. Organizations in sectors such as finance, telecommunications, government, and cloud service providers could face operational outages and potential data loss due to unexpected system crashes. The vulnerability could also affect embedded Linux systems in industrial control or telecommunications equipment prevalent in Europe. Although exploitation requires specific PCIe error conditions, accidental hardware faults or targeted attacks exploiting PCIe vulnerabilities could trigger this issue. The disruption of network interfaces can degrade availability and reliability of IT services, impacting business continuity and potentially violating regulatory requirements for uptime and data integrity in European jurisdictions.

European organizations should prioritize updating Linux kernels to versions containing the fix for CVE-2024-50040 as soon as possible. Kernel patches that implement the corrected logic in igb_io_resume() must be applied to prevent kernel panics. Network administrators should audit systems using Intel igb network adapters to identify vulnerable kernel versions. In environments where immediate patching is not feasible, monitoring PCIe error logs and network interface status can help detect early signs of the issue. Hardware diagnostics should be performed to rule out faulty PCIe devices causing non-fatal errors. Additionally, implementing PCIe error containment features and isolating critical network devices can reduce the risk of error propagation. Organizations should also consider deploying kernel crash dump analysis tools to quickly identify and respond to related panics. For high-availability environments, redundant network paths and failover mechanisms can mitigate service disruption. Finally, educating system administrators about this specific vulnerability and its symptoms will improve incident response readiness.