What happened
A high-severity vulnerability in the Linux kernel's IPv4 TCP code has been identified, with the flaw being tracked as CVE-2026-98432. The vulnerability allows a remote, unauthenticated attacker to execute code remotely, due to a use-after-free bug present in the Linux kernel. Red Hat has released fixed kernels for its Enterprise Linux versions 8, 9, and 10. Meanwhile, Ubuntu has issued fixes for its three most recent long-term-support releases, which are currently available only in testing channels, with no official date set for general deployment. The issue received public attention through reports published by The Hacker News.
Who is affected
Organisations running affected deployments of Red Hat Enterprise Linux 8, 9, or 10 are impacted by this vulnerability. Additionally, those utilizing recent Ubuntu long-term-support releases are potentially vulnerable while the fixes remain in testing channels. Affected components include the Linux kernel used in these distributions, which contains the flaw exploitable via network-based attacks without requiring user authentication.
Recommended actions
- Apply the appropriate kernel updates provided by Red Hat for versions 8, 9, and 10 as soon as they are available for production deployment.
- Monitor Ubuntu testing channels for the availability of fixed kernels, and consider testing and deploying these updates once released to stable repositories.
- Implement network controls to limit exposure of the affected systems to untrusted sources, reducing the attack surface for remote exploitation.
