Technical impact
The Linux kernel contains a flaw where the commit that handles receive packet steering incorrectly reuses a flow identifier computed elsewhere. This incorrect reuse allows the kernel to access memory beyond the bounds of the RPS table, potentially leading to a crash or loss of data integrity. The vulnerability is a classic out-of-bounds memory access (CWE-787) that can cause the operating system to become unstable or unusable.
Affected Systems
All Linux kernel builds that do not include the commit that corrects the flow-ID handling are affected. The issue does not appear to be tied to a specific kernel version; any distribution that has not applied the patch will be vulnerable.
Risk and Exploitability
The CVSS score of 9.8 indicates critical severity, as a process that can craft network packets to trigger the flawed logic could cause a kernel fault. The EPSS score is low at <1%, and the vulnerability is not listed in CISA KEV, so the publicly known exploitation probability is uncertain. The likely attack vector involves manipulating network traffic that is processed by the receive queue, which could be local or remote depending on the system configuration. System administrators should assume that any exploitation could result in a denial of service and should act quickly to mitigate.
