{"api_version":"1","generated_at":"2026-08-22T21:53:01+00:00","cve":"CVE-2026-74684","urls":{"html":"https://cve.report/CVE-2026-74684","api":"https://cve.report/api/cve/CVE-2026-74684.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-74684","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-74684"},"summary":{"title":"net: tap: set skb->dev before parsing virtio net header in tap_get_user_xdp()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: tap: set skb->dev before parsing virtio net header in tap_get_user_xdp()\n\nThe commit 4f61f133f354 (\"net: tap: NULL pointer derefence in\ndev_parse_header_protocol when skb->dev is null\") fixed a crash in\ntap_get_user() by assigning skb->dev before calling tun_vnet_hdr_to_skb().\nThis is required because virtio_net_hdr_to_skb() may invoke\ndev_parse_header_protocol(), which dereferences skb->dev. Without the\nassignment, a NULL pointer dereference can occur.\n\nHowever, tap_get_user_xdp() still parses the virtio-net header before\nassigning skb->dev. When the vhost TX path passes an XDP buffer containing\na GSO virtio-net header but the protocol is set to zero on purpose,\ntun_vnet_hdr_to_skb() can reach dev_parse_header_protocol() while skb->dev\nis still NULL, resulting in a crash.\n\nFix this by looking up the tap device and assigning skb->dev before calling\ntun_vnet_hdr_to_skb(), matching the ordering already used in\ntap_get_user(). Preserve the existing RCU read-side critical section across\ndev_queue_xmit().","state":"PUBLISHED","assigner":"Linux","published_at":"2026-08-22 16:16:42","updated_at":"2026-08-22 16:16:42"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/8b444b126cd8e4473e652f529753ed4dd1360a9c","name":"https://git.kernel.org/stable/c/8b444b126cd8e4473e652f529753ed4dd1360a9c","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/164c31ee252ebd1ac8f44c2dfc5486b6d9a0379b","name":"https://git.kernel.org/stable/c/164c31ee252ebd1ac8f44c2dfc5486b6d9a0379b","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/3874892dd27d5387aa9a06f58d9060f18f351d24","name":"https://git.kernel.org/stable/c/3874892dd27d5387aa9a06f58d9060f18f351d24","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-74684","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-74684","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 924a9bc362a5223cd448ca08c3dde21235adc310 8b444b126cd8e4473e652f529753ed4dd1360a9c git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 924a9bc362a5223cd448ca08c3dde21235adc310 164c31ee252ebd1ac8f44c2dfc5486b6d9a0379b git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 924a9bc362a5223cd448ca08c3dde21235adc310 3874892dd27d5387aa9a06f58d9060f18f351d24 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected ea3fb2ce5fa794d02135f5c079e05cd6fc3f545d git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 54ef8243c3c8e90f1ea5792e6752e021a25c8eb3 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected ca278267d6cd9544645731732455b6b20cb0e895 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected faa3baa2828c5e1c4374f3e60041f75c64f5fcb6 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 99b1d3f74b9ef72c2f74c8e4c078e1bc0706e748 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 4.14.226 4.15 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 4.19.181 4.20 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5.4.106 5.5 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5.10.24 5.11 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5.11.7 5.12 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5.12","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.12 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.45 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.1.9 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":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["drivers/net/tap.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"8b444b126cd8e4473e652f529753ed4dd1360a9c","status":"affected","version":"924a9bc362a5223cd448ca08c3dde21235adc310","versionType":"git"},{"lessThan":"164c31ee252ebd1ac8f44c2dfc5486b6d9a0379b","status":"affected","version":"924a9bc362a5223cd448ca08c3dde21235adc310","versionType":"git"},{"lessThan":"3874892dd27d5387aa9a06f58d9060f18f351d24","status":"affected","version":"924a9bc362a5223cd448ca08c3dde21235adc310","versionType":"git"},{"status":"affected","version":"ea3fb2ce5fa794d02135f5c079e05cd6fc3f545d","versionType":"git"},{"status":"affected","version":"54ef8243c3c8e90f1ea5792e6752e021a25c8eb3","versionType":"git"},{"status":"affected","version":"ca278267d6cd9544645731732455b6b20cb0e895","versionType":"git"},{"status":"affected","version":"faa3baa2828c5e1c4374f3e60041f75c64f5fcb6","versionType":"git"},{"status":"affected","version":"99b1d3f74b9ef72c2f74c8e4c078e1bc0706e748","versionType":"git"},{"lessThan":"4.15","status":"affected","version":"4.14.226","versionType":"semver"},{"lessThan":"4.20","status":"affected","version":"4.19.181","versionType":"semver"},{"lessThan":"5.5","status":"affected","version":"5.4.106","versionType":"semver"},{"lessThan":"5.11","status":"affected","version":"5.10.24","versionType":"semver"},{"lessThan":"5.12","status":"affected","version":"5.11.7","versionType":"semver"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["drivers/net/tap.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"5.12"},{"lessThan":"5.12","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.45","versionType":"semver"},{"lessThanOrEqual":"7.1.*","status":"unaffected","version":"7.1.9","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":"6.18.45","versionStartIncluding":"5.12","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.1.9","versionStartIncluding":"5.12","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2","versionStartIncluding":"5.12","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.14.226","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.19.181","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.4.106","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.10.24","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.11.7","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: tap: set skb->dev before parsing virtio net header in tap_get_user_xdp()\n\nThe commit 4f61f133f354 (\"net: tap: NULL pointer derefence in\ndev_parse_header_protocol when skb->dev is null\") fixed a crash in\ntap_get_user() by assigning skb->dev before calling tun_vnet_hdr_to_skb().\nThis is required because virtio_net_hdr_to_skb() may invoke\ndev_parse_header_protocol(), which dereferences skb->dev. Without the\nassignment, a NULL pointer dereference can occur.\n\nHowever, tap_get_user_xdp() still parses the virtio-net header before\nassigning skb->dev. When the vhost TX path passes an XDP buffer containing\na GSO virtio-net header but the protocol is set to zero on purpose,\ntun_vnet_hdr_to_skb() can reach dev_parse_header_protocol() while skb->dev\nis still NULL, resulting in a crash.\n\nFix this by looking up the tap device and assigning skb->dev before calling\ntun_vnet_hdr_to_skb(), matching the ordering already used in\ntap_get_user(). Preserve the existing RCU read-side critical section across\ndev_queue_xmit()."}],"providerMetadata":{"dateUpdated":"2026-08-22T15:32:50.846Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/8b444b126cd8e4473e652f529753ed4dd1360a9c"},{"url":"https://git.kernel.org/stable/c/164c31ee252ebd1ac8f44c2dfc5486b6d9a0379b"},{"url":"https://git.kernel.org/stable/c/3874892dd27d5387aa9a06f58d9060f18f351d24"}],"title":"net: tap: set skb->dev before parsing virtio net header in tap_get_user_xdp()","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-74684","datePublished":"2026-08-22T15:32:50.846Z","dateReserved":"2026-08-15T05:44:03.926Z","dateUpdated":"2026-08-22T15:32:50.846Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-08-22 16:16:42","lastModifiedDate":"2026-08-22 16:16:42","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"74684","Ordinal":"1","Title":"net: tap: set skb->dev before parsing virtio net header in tap_g","CVE":"CVE-2026-74684","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"74684","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: tap: set skb->dev before parsing virtio net header in tap_get_user_xdp()\n\nThe commit 4f61f133f354 (\"net: tap: NULL pointer derefence in\ndev_parse_header_protocol when skb->dev is null\") fixed a crash in\ntap_get_user() by assigning skb->dev before calling tun_vnet_hdr_to_skb().\nThis is required because virtio_net_hdr_to_skb() may invoke\ndev_parse_header_protocol(), which dereferences skb->dev. Without the\nassignment, a NULL pointer dereference can occur.\n\nHowever, tap_get_user_xdp() still parses the virtio-net header before\nassigning skb->dev. When the vhost TX path passes an XDP buffer containing\na GSO virtio-net header but the protocol is set to zero on purpose,\ntun_vnet_hdr_to_skb() can reach dev_parse_header_protocol() while skb->dev\nis still NULL, resulting in a crash.\n\nFix this by looking up the tap device and assigning skb->dev before calling\ntun_vnet_hdr_to_skb(), matching the ordering already used in\ntap_get_user(). Preserve the existing RCU read-side critical section across\ndev_queue_xmit().","Type":"Description","Title":"net: tap: set skb->dev before parsing virtio net header in tap_g"}]}}}