CVE-2024-26809 netfilter: nft_set_pipapo: release elements in clone only from destroy path

What is CVE-2024-26809?

CVE-2024-26809 is a high-severity use after free vulnerability in Debian Debian Linux, published on 4 Apr 2024. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

In the Linux kernel, the following vulnerability has been resolved:

netfilter: nft_set_pipapo: release elements in clone only from destroy path

Clone already always provides a current view of the lookup table, use it to destroy the set, otherwise it is possible to destroy elements twice.

This fix requires:

212ed75dc5fb ("netfilter: nf_tables: integrate pipapo into commit protocol")

which came after:

9827a0e6e23b ("netfilter: nft_set_pipapo: release elements in clone from abort path").

Which versions are affected by CVE-2024-26809?

It affects 2 products.

Products include Debian Debian Linux, Linux kernel.

How do I fix CVE-2024-26809?

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-2024-26809 being exploited?

There is no known exploitation of CVE-2024-26809 in the wild and no public exploit code.

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All Debian Debian Linux vulnerabilities

Sources

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

Also known as BELL-CVE-2024-26809, DEBIAN-CVE-2024-26809, GHSA-pfjp-fv5p-fjx7, UBUNTU-CVE-2024-26809.