{"api_version":"1","generated_at":"2026-08-22T00:56:21+00:00","cve":"CVE-2026-74476","urls":{"html":"https://cve.report/CVE-2026-74476","api":"https://cve.report/api/cve/CVE-2026-74476.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-74476","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-74476"},"summary":{"title":"veth: convert frag_list skbs before running XDP","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nveth: convert frag_list skbs before running XDP\n\nA frag_list skb can reach veth with data_len set but nr_frags zero.\nveth_convert_skb_to_xdp_buff() only converts skbs that are shared,\nlocked, have frags[], or do not have enough headroom. It later uses\nskb_is_nonlinear() to decide whether to set XDP_FLAGS_HAS_FRAGS and\nxdp_frags_size.\n\nThat exposes frag_list data to XDP as if it were stored in frags[], but\nfrags[] is empty. AF_XDP copy mode can then trust the bogus XDP fragment\nmetadata, walk an empty fragment entry, and crash in memcpy() from\n__xsk_rcv().\n\nRoute non-linear skbs through skb_pp_cow_data() before exposing them to\nXDP, and only advertise XDP frags when the resulting skb has frags[].\nskb_copy_bits() already handles frag_list input, and skb_pp_cow_data()\nbuilds frags[] output with skb_add_rx_frag(), which is the\nrepresentation XDP multi-buffer expects.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-08-15 13:17:52","updated_at":"2026-08-17 06:19:43"},"problem_types":[],"metrics":[{"version":"3.1","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","type":"Secondary","score":"9.1","severity":"CRITICAL","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H","data":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H","baseScore":9.1,"baseSeverity":"CRITICAL","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"NONE","availabilityImpact":"HIGH"}},{"version":"3.1","source":"CNA","type":"DECLARED","score":"9.1","severity":"CRITICAL","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H","data":{"baseScore":9.1,"baseSeverity":"CRITICAL","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H","version":"3.1"}}],"references":[{"url":"https://git.kernel.org/stable/c/d0d6415963040c401e7a7e4e482a698ba52448cb","name":"https://git.kernel.org/stable/c/d0d6415963040c401e7a7e4e482a698ba52448cb","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/f9c1fff857e93be709c8b52ed1a643f37bd82c66","name":"https://git.kernel.org/stable/c/f9c1fff857e93be709c8b52ed1a643f37bd82c66","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/b24ba0bbffe3e23eb2f6838881c1fabcb29fb9fb","name":"https://git.kernel.org/stable/c/b24ba0bbffe3e23eb2f6838881c1fabcb29fb9fb","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/5c1c15c540fc45820ce3033c319151ec891bc10a","name":"https://git.kernel.org/stable/c/5c1c15c540fc45820ce3033c319151ec891bc10a","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-74476","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-74476","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 718a18a0c8a67f97781e40bdef7cdd055c430996 5c1c15c540fc45820ce3033c319151ec891bc10a git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 718a18a0c8a67f97781e40bdef7cdd055c430996 b24ba0bbffe3e23eb2f6838881c1fabcb29fb9fb git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 718a18a0c8a67f97781e40bdef7cdd055c430996 f9c1fff857e93be709c8b52ed1a643f37bd82c66 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 718a18a0c8a67f97781e40bdef7cdd055c430996 d0d6415963040c401e7a7e4e482a698ba52448cb git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5.18","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.18 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.103 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.44 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.1.8 7.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"74476","cve":"CVE-2026-74476","epss":"0.004570000","percentile":"0.378390000","score_date":"2026-08-17","updated_at":"2026-08-18 00:11:46"},"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["drivers/net/veth.c","net/core/skbuff.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"5c1c15c540fc45820ce3033c319151ec891bc10a","status":"affected","version":"718a18a0c8a67f97781e40bdef7cdd055c430996","versionType":"git"},{"lessThan":"b24ba0bbffe3e23eb2f6838881c1fabcb29fb9fb","status":"affected","version":"718a18a0c8a67f97781e40bdef7cdd055c430996","versionType":"git"},{"lessThan":"f9c1fff857e93be709c8b52ed1a643f37bd82c66","status":"affected","version":"718a18a0c8a67f97781e40bdef7cdd055c430996","versionType":"git"},{"lessThan":"d0d6415963040c401e7a7e4e482a698ba52448cb","status":"affected","version":"718a18a0c8a67f97781e40bdef7cdd055c430996","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["drivers/net/veth.c","net/core/skbuff.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"5.18"},{"lessThan":"5.18","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.103","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.44","versionType":"semver"},{"lessThanOrEqual":"7.1.*","status":"unaffected","version":"7.1.8","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.2","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.103","versionStartIncluding":"5.18","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.44","versionStartIncluding":"5.18","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.1.8","versionStartIncluding":"5.18","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2","versionStartIncluding":"5.18","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nveth: convert frag_list skbs before running XDP\n\nA frag_list skb can reach veth with data_len set but nr_frags zero.\nveth_convert_skb_to_xdp_buff() only converts skbs that are shared,\nlocked, have frags[], or do not have enough headroom. It later uses\nskb_is_nonlinear() to decide whether to set XDP_FLAGS_HAS_FRAGS and\nxdp_frags_size.\n\nThat exposes frag_list data to XDP as if it were stored in frags[], but\nfrags[] is empty. AF_XDP copy mode can then trust the bogus XDP fragment\nmetadata, walk an empty fragment entry, and crash in memcpy() from\n__xsk_rcv().\n\nRoute non-linear skbs through skb_pp_cow_data() before exposing them to\nXDP, and only advertise XDP frags when the resulting skb has frags[].\nskb_copy_bits() already handles frag_list input, and skb_pp_cow_data()\nbuilds frags[] output with skb_add_rx_frag(), which is the\nrepresentation XDP multi-buffer expects."}],"metrics":[{"cvssV3_1":{"baseScore":9.1,"baseSeverity":"CRITICAL","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H","version":"3.1"},"scenarios":[{"lang":"en","value":"AV:N - The bug is hit when a received skb traverses veth XDP processing; in cloud/container deployments (e.g. Cloudflare-style edge nodes) remote traffic routed to a veth peer with XDP+AF_XDP can deliver the malformed frag_list skb without local access.\nAC:L - An attacker can reliably supply the required frag_list skb (data_len>0, nr_frags=0) by transmitting from the veth peer via sockets or GRO aggregation, controlling packet size, timing, and content without depending on uncontrollable kernel state.\nPR:N - Remote exploitation needs no attacker privileges when ingress traffic reaches a veth that already has an XDP program redirecting to an AF_XDP socket; only network-delivered skbs trigger veth_convert_skb_to_xdp_buff() and the faulty __xsk_rcv() path.\nUI:N - No victim user action is required beyond normal network traffic reaching the veth interface; exploitation is automatic once a qualifying frag_list skb is received and redirected to AF_XDP copy mode.\nS:U - The flaw causes kernel memory reads and crashes within the host kernel security boundary; it does not cross VM, hypervisor, or IOMMU isolation boundaries.\nC:H - Bogus XDP_FLAGS_HAS_FRAGS metadata makes __xsk_rcv() memcpy from uninitialized frags[] entries via skb_frag_address(), enabling out-of-bounds kernel memory reads into the AF_XDP receive buffer before faulting.\nI:N - The failure mode is a kernel-side memcpy read using invalid fragment metadata; data is copied into the attacker's AF_XDP ring buffer rather than corrupting kernel or other tenants' memory for integrity purposes.\nA:H - The commit and code path confirm a kernel crash when __xsk_rcv() follows bogus fragment metadata and memcpy faults on an invalid frags[] source address, causing oops/panic and denial of service."}]}],"providerMetadata":{"dateUpdated":"2026-08-17T05:47:37.441Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/5c1c15c540fc45820ce3033c319151ec891bc10a"},{"url":"https://git.kernel.org/stable/c/b24ba0bbffe3e23eb2f6838881c1fabcb29fb9fb"},{"url":"https://git.kernel.org/stable/c/f9c1fff857e93be709c8b52ed1a643f37bd82c66"},{"url":"https://git.kernel.org/stable/c/d0d6415963040c401e7a7e4e482a698ba52448cb"}],"title":"veth: convert frag_list skbs before running XDP","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-74476","datePublished":"2026-08-15T12:27:11.309Z","dateReserved":"2026-08-15T05:44:03.903Z","dateUpdated":"2026-08-17T05:47:37.441Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-08-15 13:17:52","lastModifiedDate":"2026-08-17 06:19:43","problem_types":[],"metrics":{"cvssMetricV31":[{"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H","baseScore":9.1,"baseSeverity":"CRITICAL","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"NONE","availabilityImpact":"HIGH"},"exploitabilityScore":3.9,"impactScore":5.2}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"74476","Ordinal":"1","Title":"veth: convert frag_list skbs before running XDP","CVE":"CVE-2026-74476","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"74476","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nveth: convert frag_list skbs before running XDP\n\nA frag_list skb can reach veth with data_len set but nr_frags zero.\nveth_convert_skb_to_xdp_buff() only converts skbs that are shared,\nlocked, have frags[], or do not have enough headroom. It later uses\nskb_is_nonlinear() to decide whether to set XDP_FLAGS_HAS_FRAGS and\nxdp_frags_size.\n\nThat exposes frag_list data to XDP as if it were stored in frags[], but\nfrags[] is empty. AF_XDP copy mode can then trust the bogus XDP fragment\nmetadata, walk an empty fragment entry, and crash in memcpy() from\n__xsk_rcv().\n\nRoute non-linear skbs through skb_pp_cow_data() before exposing them to\nXDP, and only advertise XDP frags when the resulting skb has frags[].\nskb_copy_bits() already handles frag_list input, and skb_pp_cow_data()\nbuilds frags[] output with skb_add_rx_frag(), which is the\nrepresentation XDP multi-buffer expects.","Type":"Description","Title":"veth: convert frag_list skbs before running XDP"}]}}}