CVE-2026-72252

Technical Description

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

netfilter: nft_set_pipapo: don't leak bad clone into future transaction

On memory allocation failure the cloned nft_pipapo_match can enter a bad

state:

- some fields can have their lookup tables resized while others did

not

- bits might have been toggled

- scratch map can be undersized which also means m->bsize_max can be

lower than what is required

This means that the next insertion in the same batch can trigger

out-of-bounds writes.

Furthermore, a failure in the first can result in the bad clone to

leak into the next transaction because the abort callback is never

executed in this case (the upper layer saw an error and no attempt to

allocate a transactional request was made).

Record a state for the nft_pipapo_match structure:

- NEW (pristine clone)

- MOD (modified clone with good state)

- ERR (potentially bogus content)

Then make it so that deletes and insertions fail when the clone

entered ERR state.

Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

References