CVE-2026-52915

A flaw was found in the Linux kernel's netfilter subsystem, specifically within the ip6t_hbh module responsible for handling IPv6 Hop-by-Hop (HBH) options. This vulnerability allows a local attacker to provide an oversized list of HBH options from userspace, leading to an out-of-bounds write. This can result in memory corruption and potentially cause a system crash, leading to a denial of service.

This vulnerability is rated as Moderate for Red Hat Enterprise Linux because exploitation requires local access with network administration privileges or the ability to create unprivileged user namespaces to manipulate firewall rules. An authenticated local user can craft a malformed rule specification containing an excessive count of IPv6 extension options, triggering an out-of-bounds array access within the kernel netfilter framework. The primary impact is limited to a kernel crash resulting in a local denial of service, without compromising data confidentiality or system integrity.

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.