A Linux kernel flaw in the handling of incoming TCP connections over IPv4 is the focus of fixes still in testing for Ubuntu 22.04, 24.04 and 26.04 LTS as of Nov.
3.
Red Hat says it could enable system crashes, denial-of-service attacks or administrator-level code execution; Canonical had not announced a stable-update date.
According to Red Hat, the issue could allow an attacker to crash an affected computer, make services unavailable through a multi-computer attack, or execute commands with administrator privileges. Servers, which are computers that support websites and other services, are most at risk. The issue is believed to have existed since 2016.
Estimates of its severity vary. The Linux kernel team rated it 9,8 out of 10, while Oracle and SUSE gave it 8,1, because they consider it more difficult to exploit.
An Anthropic researcher who first reported the issue said that an unreleased Claude model has created a working exploit. According to the researcher, an attacker located elsewhere could then gain full access to affected servers through a specific login operation.
↳
READ ALSO
HACKS.GR / RELATED
Vulnerabilities & Security Updates
SonicWall warns of two security vulnerabilities in older systems without providing a solution
↗
The delay has drawn public criticism from Ubuntu users. One developer announced in a popular post that he was moving all of his servers off Ubuntu, saying he had completely lost confidence in the distribution as a reliable and secure platform for his needs.
Canonical says it tests the fixes on thousands of certified servers and devices before releasing them. Administrators can enable the “-proposed” update section to install the fix earlier. The company says that disabling this particular login feature does not solve the problem, as it is not limited to it. It recommends installing the security update as a workaround.
In September 2026, Canonical introduced a new schedule for kernel patch updates, aiming to get them to users faster. It is possible that the new schedule's fixed testing period contributed to the delay in this particular patch.
>Stay connected with Hacks.gr
Set us as a preferred source on Google and find us on social media.
Preferred source
↗
end of article
Top comments (0)