CVE-2026-64024

A flaw was found in the Linux kernel's Transmission Control Protocol (TCP) networking stack. This vulnerability arises from a stale per-CPU variable that can retain a previously used Initial Sequence Number (ISN) when certain packets are dropped. A remote attacker could exploit this by sending specially crafted packets, leading to the prediction of subsequent ISNs. Successful exploitation of predictable ISNs can enable TCP connection hijacking, allowing an attacker to take control of existing network connections.

This vulnerability is rated as having a Moderate impact for Red Hat Enterprise Linux because successful exploitation requires highly specific packet drop conditions and precise timing on the same CPU core, rather than permitting direct kernel memory corruption or arbitrary code execution. While a remote adversary could theoretically attempt to spoof or hijack TCP sessions if sequence numbers are leaked across dropped connections, achieving reliable exploitation across multi-core systems is difficult in practice. Under standard enterprise configurations, the flaw does not facilitate broader host compromise or local privilege elevation.

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.