{"id":"CVE-2026-74616","state":"PUBLISHED","title":"xdp: reject clones that overrun skb_shared_info tailroom","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nxdp: reject clones that overrun skb_shared_info tailroom\n\nxdpf_clone() clones broadcast copies into a single page and sets\nframe_sz to PAGE_SIZE. __xdp_build_skb_from_frame() later treats that\npage like a normal XDP frame and expects the usual skb_shared_info\ntailroom at the end of the buffer.\n\nThe current check only rejects frames whose linear xdp_frame header,\nheadroom, and packet data exceed PAGE_SIZE. A source frame backed by a\nlarger allocation can still satisfy that check while extending into the\nclone's required shared-info area. When such a clone is converted back\ninto an skb, build_skb_around() places skb_shared_info over live packet\nbytes and later writes can corrupt XDP return metadata.\n\nReject clones unless their linear area fits inside\nSKB_WITH_OVERHEAD(PAGE_SIZE), matching the tailroom requirement already\nenforced by the XDP-to-skb conversion path.","publishedAt":"2026-08-22T15:32:01.313Z","updatedAt":"2026-10-16T19:06:02.219Z","severity":{"score":9.8,"label":"Critical","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"e624d4ed4aa8cc3c69d1359b0aaea539203ed266","status":"affected","lessThan":"58408982fa39f9758124cec169f42854d6f98f35","versionType":"git"},{"version":"e624d4ed4aa8cc3c69d1359b0aaea539203ed266","status":"affected","lessThan":"685edea27ac68d08fe4dbd3de74b858d2ad8e830","versionType":"git"},{"version":"e624d4ed4aa8cc3c69d1359b0aaea539203ed266","status":"affected","lessThan":"ba13763d667e008e185fedf592d53846a5b457d1","versionType":"git"},{"version":"e624d4ed4aa8cc3c69d1359b0aaea539203ed266","status":"affected","lessThan":"ef4b7c7046d29a67090de15af0da0d1ae8d1b192","versionType":"git"},{"version":"e624d4ed4aa8cc3c69d1359b0aaea539203ed266","status":"affected","lessThan":"fab820f1691a9e26d9031f18aae1e9ce09078f92","versionType":"git"},{"version":"e624d4ed4aa8cc3c69d1359b0aaea539203ed266","status":"affected","lessThan":"f463b6f4957c9c3fd1c75f8d3e5af4879fa609c0","versionType":"git"},{"version":"e624d4ed4aa8cc3c69d1359b0aaea539203ed266","status":"affected","lessThan":"e48e8edbef2eb824201495daa5234560f632b23c","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/core/xdp.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.14","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.14","versionType":"semver"},{"version":"5.15.216","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.183","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.152","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.104","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.45","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.9","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/core/xdp.c"]}],"references":["https://git.kernel.org/stable/c/58408982fa39f9758124cec169f42854d6f98f35","https://git.kernel.org/stable/c/685edea27ac68d08fe4dbd3de74b858d2ad8e830","https://git.kernel.org/stable/c/ba13763d667e008e185fedf592d53846a5b457d1","https://git.kernel.org/stable/c/ef4b7c7046d29a67090de15af0da0d1ae8d1b192","https://git.kernel.org/stable/c/fab820f1691a9e26d9031f18aae1e9ce09078f92","https://git.kernel.org/stable/c/f463b6f4957c9c3fd1c75f8d3e5af4879fa609c0","https://git.kernel.org/stable/c/e48e8edbef2eb824201495daa5234560f632b23c"],"weaknesses":[],"ingestedAt":"2026-10-29T20:12:58.252Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/74xxx/CVE-2026-74616.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-74616","state":"PUBLISHED","datePublished":"2026-08-22T15:32:01.313Z","dateUpdated":"2026-10-16T19:06:02.219Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-08-15T05:44:03.920Z"},"containers":{"cna":{"title":"xdp: reject clones that overrun skb_shared_info tailroom","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nxdp: reject clones that overrun skb_shared_info tailroom\n\nxdpf_clone() clones broadcast copies into a single page and sets\nframe_sz to PAGE_SIZE. __xdp_build_skb_from_frame() later treats that\npage like a normal XDP frame and expects the usual skb_shared_info\ntailroom at the end of the buffer.\n\nThe current check only rejects frames whose linear xdp_frame header,\nheadroom, and packet data exceed PAGE_SIZE. A source frame backed by a\nlarger allocation can still satisfy that check while extending into the\nclone's required shared-info area. When such a clone is converted back\ninto an skb, build_skb_around() places skb_shared_info over live packet\nbytes and later writes can corrupt XDP return metadata.\n\nReject clones unless their linear area fits inside\nSKB_WITH_OVERHEAD(PAGE_SIZE), matching the tailroom requirement already\nenforced by the XDP-to-skb conversion path."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"e624d4ed4aa8cc3c69d1359b0aaea539203ed266","status":"affected","lessThan":"58408982fa39f9758124cec169f42854d6f98f35","versionType":"git"},{"version":"e624d4ed4aa8cc3c69d1359b0aaea539203ed266","status":"affected","lessThan":"685edea27ac68d08fe4dbd3de74b858d2ad8e830","versionType":"git"},{"version":"e624d4ed4aa8cc3c69d1359b0aaea539203ed266","status":"affected","lessThan":"ba13763d667e008e185fedf592d53846a5b457d1","versionType":"git"},{"version":"e624d4ed4aa8cc3c69d1359b0aaea539203ed266","status":"affected","lessThan":"ef4b7c7046d29a67090de15af0da0d1ae8d1b192","versionType":"git"},{"version":"e624d4ed4aa8cc3c69d1359b0aaea539203ed266","status":"affected","lessThan":"fab820f1691a9e26d9031f18aae1e9ce09078f92","versionType":"git"},{"version":"e624d4ed4aa8cc3c69d1359b0aaea539203ed266","status":"affected","lessThan":"f463b6f4957c9c3fd1c75f8d3e5af4879fa609c0","versionType":"git"},{"version":"e624d4ed4aa8cc3c69d1359b0aaea539203ed266","status":"affected","lessThan":"e48e8edbef2eb824201495daa5234560f632b23c","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/core/xdp.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.14","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.14","versionType":"semver"},{"version":"5.15.216","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.183","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.152","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.104","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.45","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.9","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/core/xdp.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/58408982fa39f9758124cec169f42854d6f98f35"},{"url":"https://git.kernel.org/stable/c/685edea27ac68d08fe4dbd3de74b858d2ad8e830"},{"url":"https://git.kernel.org/stable/c/ba13763d667e008e185fedf592d53846a5b457d1"},{"url":"https://git.kernel.org/stable/c/ef4b7c7046d29a67090de15af0da0d1ae8d1b192"},{"url":"https://git.kernel.org/stable/c/fab820f1691a9e26d9031f18aae1e9ce09078f92"},{"url":"https://git.kernel.org/stable/c/f463b6f4957c9c3fd1c75f8d3e5af4879fa609c0"},{"url":"https://git.kernel.org/stable/c/e48e8edbef2eb824201495daa5234560f632b23c"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","baseScore":9.8,"baseSeverity":"CRITICAL"},"scenarios":[{"lang":"en","value":"AV:N - Remote packets on an XDP ingress netdev whose program calls bpf_xdp_redirect_map() with BPF_F_BROADCAST reach xdpf_clone() through dev_map_enqueue_multi(); edge L4 load balancers and container fan-out to veth peers are common deployments where cloned frames later hit __xdp_build_skb_from_frame() without any local attacker access.\nAC:L - Once broadcast devmap redirect is deployed, an attacker can reliably craft linear frames whose headroom plus payload fall in the SKB_WITH_OVERHEAD(PAGE_SIZE)..PAGE_SIZE window; no race, timing luck, or uncontrollable memory layout is required and the condition can be retried with each packet.\nPR:N - Loading/attaching the XDP program and populating the devmap requires CAP_BPF and CAP_NET_ADMIN on the host, but an unauthenticated remote sender on the already-configured datapath needs no privileges on the victim system, matching the CNA pattern used for the related devmap broadcast clone issue CVE-2026-64355.\nUI:N - Exploitation is driven entirely by network traffic processed in NAPI/softirq after XDP redirect; no victim mount, file open, or other interactive action is required beyond packets reaching the configured interface.\nS:U - The flaw corrupts skb_shared_info placement and metadata within the host kernel address space during skb construction; it does not inherently cross VM, hypervisor, or IOMMU security boundaries.\nC:H - build_skb_around() places skb_shared_info over live packet bytes and memset initializes it there; subsequent skb/shinfo access can read kernel metadata and adjacent buffer contents beyond intended bounds, constituting exploitable out-of-bounds memory disclosure.\nI:H - Overlapping skb_shared_info tailroom lets kernel writes corrupt packet data and lets attacker-influenced bytes corrupt shinfo fields used by later stack, GRO, and transmit paths, giving an out-of-bounds write primitive over frame metadata.\nA:H - Tailroom overlap during __xdp_build_skb_from_frame() can fault or corrupt state during skb construction and downstream processing, producing kernel oops/panic; an attacker can trigger this repeatedly with crafted packets on the broadcast redirect path."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-25T05:40:43.432Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.14","versionEndExcluding":"5.15.216"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.14","versionEndExcluding":"6.1.183"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.14","versionEndExcluding":"6.6.152"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.14","versionEndExcluding":"6.12.104"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.14","versionEndExcluding":"6.18.45"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.14","versionEndExcluding":"7.1.9"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.14","versionEndExcluding":"7.2"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2026-74616","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"total"}],"version":"2.0.3","timestamp":"2026-10-16T19:02:32.968446Z"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-16T19:06:02.219Z"}}]}}}