by Kastro
Paper/Archive/CVE-2026-72320

CVE-2026-72320

Linux Linux — netfilter: nft_lookup: fix catchall element handling with inverted lookups

EPSS 0.5%CVSS 9.1
critical.is priorityof 100
36
CVSS 9.1 (CNA)9.1 / 10 × 3027.3Not in CISA KEV+300.0EPSS percentile 44.3.443 × 208.9No public exploit+100.0SSVC exploitation: none+100.0
Description · from the CVE record

In the Linux kernel, the following vulnerability has been resolved: netfilter: nft_lookup: fix catchall element handling with inverted lookups nft_lookup_eval() decides whether a lookup matched (`found`) from the direct set lookup and priv->invert before falling back to the catchall element used by interval sets (e.g. nft_set_rbtree) for the open-ended default range. Since `found` is never recomputed after `ext` is replaced by the catchall lookup, inverted lookups (NFT_LOOKUP_F_INV, "!= @set") can wrongly match or wrongly skip the catchall element, producing the wrong verdict. Fold the catchall lookup into `ext` before computing `found`, matching the order already used by nft_objref_map_eval().

Affected

ProductAffectedFixed inSource
Linuxaaa31047a6d25da0fa101da1ed544e1247949b40 – < 65d35cb555f40529a9edc6bf4beaa3bee917f01565d35cb555f40529a9edc6bf4beaa3bee917f015CNA
Linuxaaa31047a6d25da0fa101da1ed544e1247949b40 – < 0ab8880865f9678eb6174e72c1fc4712e44c745c0ab8880865f9678eb6174e72c1fc4712e44c745cCNA
Linuxaaa31047a6d25da0fa101da1ed544e1247949b40 – < 238c612357b5a25f03eacf356f95034f8551f218238c612357b5a25f03eacf356f95034f8551f218CNA
Linuxaaa31047a6d25da0fa101da1ed544e1247949b40 – < ef0c7d4b04a0e6ad175323c24bc84e11470dd79def0c7d4b04a0e6ad175323c24bc84e11470dd79dCNA
Linuxaaa31047a6d25da0fa101da1ed544e1247949b40 – < e6107a4c74b54cb33e3bce162a63048ae5a6b198e6107a4c74b54cb33e3bce162a63048ae5a6b198CNA
Linux5.13–CNA

Scores by source

Linux (CNA)9.1CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
CISA ADPSSVCExploitation: none · Automatable: yes · Technical impact: total

References

refgit.kernel.org/stable/c/65d35cb555f40529a9edc6bf4beaa3bee917f015refgit.kernel.org/stable/c/0ab8880865f9678eb6174e72c1fc4712e44c745crefgit.kernel.org/stable/c/238c612357b5a25f03eacf356f95034f8551f218refgit.kernel.org/stable/c/ef0c7d4b04a0e6ad175323c24bc84e11470dd79drefgit.kernel.org/stable/c/e6107a4c74b54cb33e3bce162a63048ae5a6b198