CVE-2026-68136

A flaw was found in the Linux kernel's Generic Receive Offload (GRO) networking subsystem. An attacker could exploit this by sending specially crafted network packets that cause a double aggregation of flush-marked socket buffers (skbs). This issue arises from a missing flush check, which allows already-processed packets to be re-aggregated, corrupting the internal data structure. This corruption leads to an invalid state when the system attempts to process these packets, triggering a kernel panic and resulting in a Denial of Service (DoS).

This vulnerability is rated as Important because untrusted network traffic forwarded through an affected host can trigger an unhandled kernel crash, causing a full denial of service without requiring administrative privileges. In Red Hat Enterprise Linux environments, exposure is highest on hosts configured for packet routing, device forwarding, or containerized network bridges where Generic Receive Offload and packet re-segmentation across multiple interfaces are active. Standard endpoints that terminate network connections locally rather than routing packets between interfaces experience reduced exposure, as the failure primarily manifests during transmission segmentation of forwarded frames.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.