Description
In the Linux kernel, the following vulnerability has been resolved: netfilter: bridge: release template ct on non-IP path A bridge nftables ct zone set rule can attach a conntrack template to an skb before nf_ct_bridge_pre() sees it. For non-IPv4 and non-IPv6 EtherTypes, nf_ct_bridge_pre() currently overwrites skb->_nfct with IP_CT_UNTRACKED without releasing the existing template reference. That makes the per-cpu template, and any temporary templates allocated for concurrent use, unreachable and leaks memory until the host runs out of slab. Reset the skb conntrack state before marking the frame untracked so the existing template reference is dropped on the non-IP path.
References8
- git.kernel.org/stable/c/46d559f00b1ab1d114f92d2f16c5ef0093b3b9dd
- git.kernel.org/stable/c/6ea88401e10e04e0b3bb7a7adea54932fb60b93b
- git.kernel.org/stable/c/7cff440d702616022769f2643168d7f9820547a0
- git.kernel.org/stable/c/bd7b16494dacf87e9336a1dcfdada83b9e40edd6
- git.kernel.org/stable/c/c58d34fe8b7e47bb0b350a7625023b1261342be5
- git.kernel.org/stable/c/d45cc8020d7c0a9f01dee42ff5c40bc14c9af72f
- git.kernel.org/stable/c/daa6e070f8e1e7a4dddec8b64ca37663f8cda917
- git.kernel.org/stable/c/fc90df37540627d092af770215fb4b7befe9409b
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 1% percentile: 43 · as of 9 November 2026
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