{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-90146", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-11T19:38:34.789Z", "datePublished": "2026-09-17T16:06:41.695Z", "dateUpdated": "2026-10-21T12:50:04.647Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-21T12:50:04.647Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf, xdp: move offload check into dev_xdp_install()\n\nbpf_xdp_link_update() calls dev_xdp_install() directly and skips\ndev_xdp_attach(), so the checks in dev_xdp_attach() do not run. A user can\nmake an XDP link with a normal program and then swap in an offloaded or\ndevice-bound program with BPF_LINK_UPDATE, which puts it on the software\npath.\n\ndev_xdp_install() is the one place all three paths go through:\n\"ip link set xdp\" and BPF_LINK_CREATE reach it via dev_xdp_attach(), and\nBPF_LINK_UPDATE calls it directly. So move the program checks (offloaded,\nbound to another device, device-bound in generic mode, native vs generic,\nDEVMAP and CPUMAP) there, and keep only the netlink-flag check\n(XDP_FLAGS_UPDATE_IF_NOEXIST) in dev_xdp_attach()." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - The attacker-controlled data is the replacement program fd on bpf(BPF_LINK_UPDATE), which __sys_bpf() dispatches to link_update() then bpf_xdp_link_update() in net/core/dev.c; that local syscall installs the prog, rather than a parsed ksmbd/nfsd/packet payload.\nAC:L - bpf_xdp_link_update() only compares prog->type and expected_attach_type, so BPF_LINK_CREATE of a normal XDP prog on a veth with XDP_FLAGS_SKB_MODE followed by BPF_LINK_UPDATE of a BPF_F_XDP_DEV_BOUND_ONLY prog that calls bpf_xdp_metadata_rx_* always bypasses the skipped dev_xdp_attach() checks, with no race.\nPR:L - bpf_prog_load() of BPF_PROG_TYPE_XDP requires bpf_token_capable(CAP_BPF) and bpf_token_capable(CAP_NET_ADMIN) before bpf_xdp_link_attach()/link_update(); those caps, and the CAP_NET_ADMIN to add the veth attach target, are obtainable in a user/netns via unshare and BPF token delegation, not only init-namespace root.\nUI:N - The attacker loads both programs, creates the XDP link, calls BPF_LINK_UPDATE, and then drives do_xdp_generic() by sending a frame through their own veth peer; no victim mount, file open, or other cooperative action is required.\nS:U - The confused metadata kfuncs (veth_xdp_rx_hash() and friends) run in the host kernel XDP path do_xdp_generic()/bpf_prog_run_generic_xdp() and corrupt host kernel memory; this is not a KVM/Xen guest-to-host escape or an IOMMU/DMA boundary bypass.\nC:H - After the skipped bpf_prog_is_dev_bound() checks, a veth-bound program can run on generic XDP's stack struct xdp_buff; veth_xdp_rx_timestamp()/veth_xdp_rx_vlan_tag() cast it to veth_xdp_buff and read skb_hwtstamps()/vlan fields through that bogus skb pointer, an unbounded kernel read into BPF maps.\nI:H - The same confused veth_xdp_buff.skb is passed to skb_get_hash(), which writes hash/sw_hash/l4_hash via __skb_get_hash_net(); swapping a veth-bound prog onto mlx5 native XDP likewise treats mlx5e_xdp_buff.cqe as an sk_buff and writes into the CQE, which is type confusion with a kernel write.\nA:H - do_xdp_generic() allocates a bare struct xdp_buff, so the next RX after the bad BPF_LINK_UPDATE makes veth_xdp_rx_hash() or mlx5e_xdp_rx_timestamp() dereference adjacent stack/wrapper bytes as skb, cqe, or rq and oops; an offloaded prog swapped onto the software path also hits bpf_prog_warn_on_exec() per packet." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/core/dev.c" ], "versions": [ { "version": "026a4c28e1db3b0cb99cd9a3e495d4a8b632fa74", "lessThan": "bd06033625ec20b7bdec43d21f776fc1a5e9000e", "status": "affected", "versionType": "git" }, { "version": "026a4c28e1db3b0cb99cd9a3e495d4a8b632fa74", "lessThan": "486dbe7efec2be19cd3625be282f7f6b34a3f2c5", "status": "affected", "versionType": "git" }, { "version": "026a4c28e1db3b0cb99cd9a3e495d4a8b632fa74", "lessThan": "f14b774ec9bd52d0f4ec29a6597a35fd107197f9", "status": "affected", "versionType": "git" }, { "version": "026a4c28e1db3b0cb99cd9a3e495d4a8b632fa74", "lessThan": "ea7b35dcc9430293b861bc7bad0c546f193c85f9", "status": "affected", "versionType": "git" }, { "version": "026a4c28e1db3b0cb99cd9a3e495d4a8b632fa74", "lessThan": "03022dd874070768a7099f18b1944c633641315f", "status": "affected", "versionType": "git" }, { "version": "026a4c28e1db3b0cb99cd9a3e495d4a8b632fa74", "lessThan": "ad27ed7d2309419a129078d781504f486b1b469a", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/core/dev.c" ], "versions": [ { "version": "5.9", "status": "affected" }, { "version": "0", "lessThan": "5.9", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.160", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.113", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.114", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.52", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2.6", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.3", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.9", "versionEndExcluding": "6.6.160" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.9", "versionEndExcluding": "6.12.113" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.9", "versionEndExcluding": "6.12.114" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.9", "versionEndExcluding": "6.18.52" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.9", "versionEndExcluding": "7.2.6" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.9", "versionEndExcluding": "7.3" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/bd06033625ec20b7bdec43d21f776fc1a5e9000e" }, { "url": "https://git.kernel.org/stable/c/486dbe7efec2be19cd3625be282f7f6b34a3f2c5" }, { "url": "https://git.kernel.org/stable/c/f14b774ec9bd52d0f4ec29a6597a35fd107197f9" }, { "url": "https://git.kernel.org/stable/c/ea7b35dcc9430293b861bc7bad0c546f193c85f9" }, { "url": "https://git.kernel.org/stable/c/03022dd874070768a7099f18b1944c633641315f" }, { "url": "https://git.kernel.org/stable/c/ad27ed7d2309419a129078d781504f486b1b469a" } ], "title": "bpf, xdp: move offload check into dev_xdp_install()", "x_generator": { "engine": "bippy-1.2.0" } } } }