CVE-2026-74625

Summary

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.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux3c171f496ef57774f8e5d509923372549734877f < fc90df37540627d092af770215fb4b7befe9409baffected
LinuxLinux3c171f496ef57774f8e5d509923372549734877f < daa6e070f8e1e7a4dddec8b64ca37663f8cda917affected
LinuxLinux3c171f496ef57774f8e5d509923372549734877f < bd7b16494dacf87e9336a1dcfdada83b9e40edd6affected
LinuxLinux3c171f496ef57774f8e5d509923372549734877f < 6ea88401e10e04e0b3bb7a7adea54932fb60b93baffected
LinuxLinux3c171f496ef57774f8e5d509923372549734877f < 46d559f00b1ab1d114f92d2f16c5ef0093b3b9ddaffected
LinuxLinux3c171f496ef57774f8e5d509923372549734877f < c58d34fe8b7e47bb0b350a7625023b1261342be5affected
LinuxLinux3c171f496ef57774f8e5d509923372549734877f < 7cff440d702616022769f2643168d7f9820547a0affected
LinuxLinux3c171f496ef57774f8e5d509923372549734877f < d45cc8020d7c0a9f01dee42ff5c40bc14c9af72faffected
LinuxLinux5.3affected
LinuxLinux0 < 5.3unaffected
LinuxLinux5.10.265 <= 5.10.*unaffected
LinuxLinux5.15.216 <= 5.15.*unaffected
LinuxLinux6.1.183 <= 6.1.*unaffected
LinuxLinux6.6.152 <= 6.6.*unaffected
LinuxLinux6.12.104 <= 6.12.*unaffected
LinuxLinux6.18.45 <= 6.18.*unaffected
LinuxLinux7.1.9 <= 7.1.*unaffected
LinuxLinux7.2 <= *unaffected

Weaknesses

References