In the Linux kernel, the following vulnerability has been resolved: netfilter: conntrack: tcp: use UNACK timeout for non-closing RST packets Commit be0502a3f2e9 ("netfilter: conntrack: tcp: only close if RST matches exact sequence") keeps an established conntrack entry in ESTABLISHED when an in-window RST does not match the expected sequence number …

Technical analysis of the CVE-2026-98625 Linux netfilter flowtable use-after-free.

CVE-2026-80668 is a remote Linux kernel use-after-free in netfilter conntrack, CVSS 9.8. The stock CentOS 7 kernel is affected with no update. The fix is kernel-lt 6.18.62, free for any use.

CVE-2026-80668 is a use-after-free in Linux netfilter connection tracking: an expectation created by a protocol helper (FTP, SIP, H.323) can outlive its master connection. The kernel.org CNA rates it CVSS 9.8, remote and unauthenticated. Red Hat rates it Moderate. On CentOS 7 it reaches the kernel most servers still run: * **Stock 3.10:** affected, per Red Hat, and CentOS 7 gets no kernel updates. Automatic helper assignment is still on (`net.netfilter.nf_conntrack_helper = 1`). In a test VM, enabling firewalld's `ftp` service and sending one `PASV` from an unauthenticated client created the object this bug frees too early. * **ELRepo`kernel-lt` 5.4.278 and `kernel-ml` 6.9.7:** outside this CVE's affected range, but both carry CVE-2026-99270, a remote TCP use-after-free, and get no more builds. ## The fix Disclosure: I maintain this package. GetPageSpeed's `kernel-lt` 6.18.62 uses the same package name, installs beside your current kernel, and is free for any use: yum -y install https://extras.getpagespeed.com/release-latest.rpm yum -y install yum-utils yum-config-manager --enable getpagespeed-extras-corecare yum -y install kernel-lt grub2-set-default 0 grubby --default-kernel reboot Already on our 6.18 kernel? `yum -y update 'kernel-lt*'` is enough: 6.18.62-2 makes the new kernel the GRUB default itself, which earlier packages did not. I ran both paths on CentOS 7 VMs against the live repository. The exposure checks, a stopgap for servers you cannot reboot yet, and the rollback are in the full write-up.

Google's kernelCTF program has published full technical details and a working proof-of-concept exploit for CVE-2026-23111. This Linux nf_tables vulnerability is a use-after-free bug in the kernel's Netfilter packet filter. A local attacker can use it to gain root and escape a container. Red Hat rates the flaw 7.8 (High) on the CVSS scale. TL;DR A one-character logic error lets an attacker drain a chain's reference count.