{"api_version":"1","generated_at":"2026-08-22T21:53:00+00:00","cve":"CVE-2026-74668","urls":{"html":"https://cve.report/CVE-2026-74668","api":"https://cve.report/api/cve/CVE-2026-74668.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-74668","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-74668"},"summary":{"title":"packet: use consistent hard_header_len in TX_RING send path","description":"In the Linux kernel, the following vulnerability has been resolved:\n\npacket: use consistent hard_header_len in TX_RING send path\n\ntpacket_snd() reads dev->hard_header_len independently for skb\nallocation and header construction in tpacket_fill_skb(). Concurrent\nnetdevice reconfiguration can therefore make the reserved headroom\nsmaller than the amount later pushed, or make copylen - hard_header_len\nnegative.\n\nSnapshot hard_header_len once before processing ring frames and use it\nfor the frame limit, headroom allocation, copy length, and skb\nconstruction. Pass the snapshot to tpacket_fill_skb().\n\nThe separate SOCK_DGRAM consistency problem between hard_header_len and\nheader_ops->create is not addressed here.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-08-22 16:16:40","updated_at":"2026-08-22 16:16:40"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/d48ea5c9c4c34dc0df621f0e39ed3a16b644621a","name":"https://git.kernel.org/stable/c/d48ea5c9c4c34dc0df621f0e39ed3a16b644621a","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/21b5953e7494c16a42e6cd8cf110e18d13ae4a6b","name":"https://git.kernel.org/stable/c/21b5953e7494c16a42e6cd8cf110e18d13ae4a6b","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/016763e829cac37b3234eace86fd0a4c560de4a7","name":"https://git.kernel.org/stable/c/016763e829cac37b3234eace86fd0a4c560de4a7","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/d85d2fd54e901637c81d847811e03c662aee13cd","name":"https://git.kernel.org/stable/c/d85d2fd54e901637c81d847811e03c662aee13cd","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/27e068d1b35dbec10a3cf268887c94407be4badc","name":"https://git.kernel.org/stable/c/27e068d1b35dbec10a3cf268887c94407be4badc","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-74668","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-74668","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 69e3c75f4d541a6eb151b3ef91f34033cb3ad6e1 d85d2fd54e901637c81d847811e03c662aee13cd git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 69e3c75f4d541a6eb151b3ef91f34033cb3ad6e1 016763e829cac37b3234eace86fd0a4c560de4a7 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 69e3c75f4d541a6eb151b3ef91f34033cb3ad6e1 27e068d1b35dbec10a3cf268887c94407be4badc git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 69e3c75f4d541a6eb151b3ef91f34033cb3ad6e1 d48ea5c9c4c34dc0df621f0e39ed3a16b644621a git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 69e3c75f4d541a6eb151b3ef91f34033cb3ad6e1 21b5953e7494c16a42e6cd8cf110e18d13ae4a6b git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 2.6.31","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 2.6.31 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.6.152 6.6.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.104 6.12.* 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":["net/packet/af_packet.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"d85d2fd54e901637c81d847811e03c662aee13cd","status":"affected","version":"69e3c75f4d541a6eb151b3ef91f34033cb3ad6e1","versionType":"git"},{"lessThan":"016763e829cac37b3234eace86fd0a4c560de4a7","status":"affected","version":"69e3c75f4d541a6eb151b3ef91f34033cb3ad6e1","versionType":"git"},{"lessThan":"27e068d1b35dbec10a3cf268887c94407be4badc","status":"affected","version":"69e3c75f4d541a6eb151b3ef91f34033cb3ad6e1","versionType":"git"},{"lessThan":"d48ea5c9c4c34dc0df621f0e39ed3a16b644621a","status":"affected","version":"69e3c75f4d541a6eb151b3ef91f34033cb3ad6e1","versionType":"git"},{"lessThan":"21b5953e7494c16a42e6cd8cf110e18d13ae4a6b","status":"affected","version":"69e3c75f4d541a6eb151b3ef91f34033cb3ad6e1","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["net/packet/af_packet.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"2.6.31"},{"lessThan":"2.6.31","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.6.*","status":"unaffected","version":"6.6.152","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.104","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":"6.6.152","versionStartIncluding":"2.6.31","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.104","versionStartIncluding":"2.6.31","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.45","versionStartIncluding":"2.6.31","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.1.9","versionStartIncluding":"2.6.31","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2","versionStartIncluding":"2.6.31","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\npacket: use consistent hard_header_len in TX_RING send path\n\ntpacket_snd() reads dev->hard_header_len independently for skb\nallocation and header construction in tpacket_fill_skb(). Concurrent\nnetdevice reconfiguration can therefore make the reserved headroom\nsmaller than the amount later pushed, or make copylen - hard_header_len\nnegative.\n\nSnapshot hard_header_len once before processing ring frames and use it\nfor the frame limit, headroom allocation, copy length, and skb\nconstruction. Pass the snapshot to tpacket_fill_skb().\n\nThe separate SOCK_DGRAM consistency problem between hard_header_len and\nheader_ops->create is not addressed here."}],"providerMetadata":{"dateUpdated":"2026-08-22T15:32:39.583Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/d85d2fd54e901637c81d847811e03c662aee13cd"},{"url":"https://git.kernel.org/stable/c/016763e829cac37b3234eace86fd0a4c560de4a7"},{"url":"https://git.kernel.org/stable/c/27e068d1b35dbec10a3cf268887c94407be4badc"},{"url":"https://git.kernel.org/stable/c/d48ea5c9c4c34dc0df621f0e39ed3a16b644621a"},{"url":"https://git.kernel.org/stable/c/21b5953e7494c16a42e6cd8cf110e18d13ae4a6b"}],"title":"packet: use consistent hard_header_len in TX_RING send path","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-74668","datePublished":"2026-08-22T15:32:39.583Z","dateReserved":"2026-08-15T05:44:03.924Z","dateUpdated":"2026-08-22T15:32:39.583Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-08-22 16:16:40","lastModifiedDate":"2026-08-22 16:16:40","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"74668","Ordinal":"1","Title":"packet: use consistent hard_header_len in TX_RING send path","CVE":"CVE-2026-74668","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"74668","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\npacket: use consistent hard_header_len in TX_RING send path\n\ntpacket_snd() reads dev->hard_header_len independently for skb\nallocation and header construction in tpacket_fill_skb(). Concurrent\nnetdevice reconfiguration can therefore make the reserved headroom\nsmaller than the amount later pushed, or make copylen - hard_header_len\nnegative.\n\nSnapshot hard_header_len once before processing ring frames and use it\nfor the frame limit, headroom allocation, copy length, and skb\nconstruction. Pass the snapshot to tpacket_fill_skb().\n\nThe separate SOCK_DGRAM consistency problem between hard_header_len and\nheader_ops->create is not addressed here.","Type":"Description","Title":"packet: use consistent hard_header_len in TX_RING send path"}]}}}