CVE-2023-6817 Use-after-free in Linux kernel's netfilter: nf_tables component

What is CVE-2023-6817?

CVE-2023-6817 is a high-severity use after free vulnerability in Linux kernel, published on 18 Dec 2023. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

A use-after-free vulnerability in the Linux kernel's netfilter: nf_tables component can be exploited to achieve local privilege escalation.

The function nft_pipapo_walk did not skip inactive elements during set walk which could lead double deactivations of PIPAPO (Pile Packet Policies) elements, leading to use-after-free.

We recommend upgrading past commit 317eb9685095678f2c9f5a8189de698c5354316a.

Weakness: CWE-416

Which versions are affected by CVE-2023-6817?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2023-6817?

Apply the vendor's patch.

Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.

Is CVE-2023-6817 being exploited?

There is no known exploitation of CVE-2023-6817 in the wild and no public exploit code.

Other vulnerabilities in Linux kernel

• CVE-2026-53266 Linux Kernel Out-of-Bounds Write Exploited High 8.8
• CVE-2013-6282 Linux Kernel Improper Input Validation Exploited High 8.8
• CVE-2022-0185 Linux Kernel Heap-Based Buffer Overflow Exploited High 8.4
• CVE-2013-2094 Linux Kernel Privilege Escalation Exploited High 8.4
• CVE-2026-53362 Linux Kernel Unspecified Exploited High 7.8

All Linux kernel vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as AZL-62609, BELL-CVE-2023-6817, DEBIAN-CVE-2023-6817, GHSA-j5r4-2mjg-6xcc, UBUNTU-CVE-2023-6817.