{ "schema_version": "1.6.1", "id": "RPI-CVE-2026-74260", "modified": "2026-10-09T11:39:44Z", "upstream": [ "CVE-2026-74260" ], "published": "2026-08-15T06:04:33Z", "summary": "netfilter: nf_dup_netdev: add nf_dev_xmit_recursion*() helpers and use them", "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nf_dup_netdev: add nf_dev_xmit_recursion*() helpers and use them\n\nUpdate nft_dup and nft_fwd to use the nf_dev_xmit_recursion() helpers.\nThis patch also disables BH when transmitting the skb to address a\npossible migration to different CPU leading to imbalanced decrementation\nof the recursion counters.\n\nThis is modeled after Florian Westphal's dev_xmit_recursion*() API\navailable since commit 97cdcf37b57e (\"net: place xmit recursion in\nsoftnet data\") according to its current state in the tree.", "severity": [ { "type": "CVSS_V3", "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H" } ], "affected": [ { "package": { "ecosystem": "Raspberry Pi OS:13", "name": "linux" }, "versions": [ "1:6.18.29-1+rpt1", "1:6.18.33-1+rpt1", "1:6.18.34-1+rpt1", "1:6.18.39-1+rpt1", "1:6.18.50-1+rpt1" ], "ecosystem_specific": { "binaries": [ { "binary_name": "linux-image-6.18.29+rpt-rpi-2712", "binary_version": "1:6.18.29-1+rpt1" }, { "binary_name": "linux-image-6.18.29+rpt-rpi-v6", "binary_version": "1:6.18.29-1+rpt1" }, { "binary_name": "linux-image-6.18.29+rpt-rpi-v7", "binary_version": "1:6.18.29-1+rpt1" }, { "binary_name": "linux-image-6.18.29+rpt-rpi-v8", "binary_version": "1:6.18.29-1+rpt1" }, { "binary_name": "linux-image-6.18.29+rpt-rpi-v8-rt", "binary_version": "1:6.18.29-1+rpt1" }, { "binary_name": "linux-image-6.18.33+rpt-rpi-2712", "binary_version": "1:6.18.33-1+rpt1" }, { "binary_name": "linux-image-6.18.33+rpt-rpi-v6", "binary_version": "1:6.18.33-1+rpt1" }, { "binary_name": "linux-image-6.18.33+rpt-rpi-v7", "binary_version": "1:6.18.33-1+rpt1" }, { "binary_name": "linux-image-6.18.33+rpt-rpi-v8", "binary_version": "1:6.18.33-1+rpt1" }, { "binary_name": "linux-image-6.18.33+rpt-rpi-v8-rt", "binary_version": "1:6.18.33-1+rpt1" }, { "binary_name": "linux-image-6.18.34+rpt-rpi-2712", "binary_version": "1:6.18.34-1+rpt1" }, { "binary_name": "linux-image-6.18.34+rpt-rpi-v6", "binary_version": "1:6.18.34-1+rpt1" }, { "binary_name": "linux-image-6.18.34+rpt-rpi-v7", "binary_version": "1:6.18.34-1+rpt1" }, { "binary_name": "linux-image-6.18.34+rpt-rpi-v8", "binary_version": "1:6.18.34-1+rpt1" }, { "binary_name": "linux-image-6.18.34+rpt-rpi-v8-rt", "binary_version": "1:6.18.34-1+rpt1" }, { "binary_name": "linux-image-6.18.39+rpt-rpi-2712", "binary_version": "1:6.18.39-1+rpt1" }, { "binary_name": "linux-image-6.18.39+rpt-rpi-v6", "binary_version": "1:6.18.39-1+rpt1" }, { "binary_name": "linux-image-6.18.39+rpt-rpi-v7", "binary_version": "1:6.18.39-1+rpt1" }, { "binary_name": "linux-image-6.18.39+rpt-rpi-v8", "binary_version": "1:6.18.39-1+rpt1" }, { "binary_name": "linux-image-6.18.39+rpt-rpi-v8-rt", "binary_version": "1:6.18.39-1+rpt1" }, { "binary_name": "linux-image-6.18.50+rpt-rpi-2712", "binary_version": "1:6.18.50-1+rpt1" }, { "binary_name": "linux-image-6.18.50+rpt-rpi-v6", "binary_version": "1:6.18.50-1+rpt1" }, { "binary_name": "linux-image-6.18.50+rpt-rpi-v7", "binary_version": "1:6.18.50-1+rpt1" }, { "binary_name": "linux-image-6.18.50+rpt-rpi-v8", "binary_version": "1:6.18.50-1+rpt1" }, { "binary_name": "linux-image-6.18.50+rpt-rpi-v8-rt", "binary_version": "1:6.18.50-1+rpt1" } ] }, "database_specific": { "per_version": { "1:6.18.29-1+rpt1": { "linux_commit": "66318c5b5cd8145a662303af12ed39ac07eb27cc", "upstream_version": "6.18.29", "assessment": "commit ancestry (strak rule)", "upstream_fixed": null }, "1:6.18.33-1+rpt1": { "linux_commit": "95b85bebbedcaedfa7ca79116ed38b7376fba412", "upstream_version": "6.18.33", "assessment": "commit ancestry (strak rule)", "upstream_fixed": null }, "1:6.18.34-1+rpt1": { "linux_commit": "c8c7494100e99ee05b11aaa4f0588a223a63d1af", "upstream_version": "6.18.34", "assessment": "commit ancestry (strak rule)", "upstream_fixed": null }, "1:6.18.39-1+rpt1": { "linux_commit": "60ea684a8ace97bb0db1a16e20753bdd6ab371ff", "upstream_version": "6.18.39", "assessment": "commit ancestry (strak rule)", "upstream_fixed": null }, "1:6.18.50-1+rpt1": { "linux_commit": "cff533aec2fa601846766b32ff57204e0a61bed7", "upstream_version": "6.18.50", "assessment": "commit ancestry (strak rule)", "upstream_fixed": null } } } } ], "references": [ { "type": "ADVISORY", "url": "https://www.cve.org/CVERecord?id=CVE-2026-74260" }, { "type": "FIX", "url": "https://git.kernel.org/stable/c/edf234f71fb327792196f813048ab8f5bd3bb712" }, { "type": "FIX", "url": "https://git.kernel.org/stable/c/2354e975932dabb06fad239f07a3b68fd1809737" } ], "database_specific": { "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git", "upstream_modified": "2026-08-17T05:50:24Z", "severity": { "source": "kernel CNA", "cvss_v3_score": 7.8, "cvss_v3_severity": "High", "scenario": "AV:L - The flaw is reached through nftables netdev fwd/dup evaluation on NF_NETDEV ingress/egress hooks installed via nfnetlink; kernel CNA guidance treats netfilter/nftables configuration and packet-hook paths as Local even when traffic ultimately arrives from the network.\nAC:L - An attacker with CAP_NET_ADMIN can deterministically install netdev egress/ingress fwd or dup rules that loop (same device or mutual forwarding) and drive packets through them; concurrent traffic also lets the attacker influence CPU migration that desynchronizes the per-CPU recursion counter without uncontrollable races.\nPR:L - Installing netdev nftables fwd/dup rules requires CAP_NET_ADMIN via nfnetlink (netlink_net_capable), but that capability is routinely obtainable in an unprivileged-created user+network namespace (unshare -Urn) and is commonly delegated to containers with NET_ADMIN.\nUI:N - Exploitation needs only the attacker's own nftables/netlink setup and packet injection; no victim must mount filesystems, open files, click prompts, or perform any deliberate interactive action beyond ordinary traffic delivery.\nS:U - Impact is unbounded kernel-stack recursion and crash/panic within the same kernel security domain; it does not cross a VM, container, IOMMU, or other distinct security-authority boundary such as guest-to-host escape.\nC:H - Bypassing the nf_dup_skb_recursion limit allows unbounded nf_hook_egress/ingress re-entry that corrupts kernel stack frames before the guard page; such stack corruption can disclose adjacent kernel memory and is not a pure NULL-deref crash with no data exposure.\nI:H - Unbounded recursion overflows the kernel task stack and overwrites saved return addresses/control data on the stack, providing a standard path to arbitrary kernel writes and control-flow hijack rather than a bounded or crash-only integrity effect.\nA:H - When the per-CPU recursion counter is desynchronized by CPU migration without local_bh_disable(), fwd/dup netdev rules can recurse without bound through neigh_xmit/dev_queue_xmit and nf_hook_egress, exhausting the kernel stack and causing oops/panic." } } }