CVE-2026-64024
Description
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.
Statement
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.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 7 | N/A | 9.4 |
| Attack Vector | Local | N/A | Network |
| Attack Complexity | High | N/A | Low |
| Privileges Required | Low | N/A | None |
| User Interaction | None | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | High | N/A | Low |
| Integrity Impact | High | N/A | High |
| Availability Impact | High | N/A | High |
Vector
Red Hat: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:H
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