The Linux kernel contains a flaw that causes ICMP extended echo reply packets to be processed without first verifying the packet’s type. Because the ICMP extension type is greater than the range handled by the icmp_pointers array, the code may look up outside that array bounds. This can lead to an out‑of‑bounds memory access that may expose kernel memory contents or overwrite pointers, potentially allowing an attacker to gain kernel execution or cause a crash. The weakness corresponds to an unvalidated array index situation.

All Linux kernels running the unpatched code before the commit that added validation are affected. The vulnerability is present in the mainline kernel until the fix is merged; administrators should verify that their kernel version includes the patch referenced in the provided commit links. Exact version ranges are not specified in the data.

The EPSS score is < 1% and the vulnerability is not listed in CISA’s KEV catalog, so its current exploitation probability is low. However, the likely attack vector is by sending crafted ICMP extended echo reply packets from an external host, inferred from the nature of the vulnerability. The CVSS score of 8.2 indicates high severity, meaning that while the flaw is serious, it still may not be widely exploited but poses a strong risk that could compromise system integrity if exploited.