{"api_version":"1","generated_at":"2026-08-22T00:56:20+00:00","cve":"CVE-2026-74582","urls":{"html":"https://cve.report/CVE-2026-74582","api":"https://cve.report/api/cve/CVE-2026-74582.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-74582","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-74582"},"summary":{"title":"packet: use consistent hard_header_len in non-ring send paths","description":"In the Linux kernel, the following vulnerability has been resolved:\n\npacket: use consistent hard_header_len in non-ring send paths\n\npacket_snd() reads dev->hard_header_len multiple times while allocating\nand constructing an skb. Device reconfiguration can change this value\nconcurrently, for example through bonding device type changes.\n\nFor SOCK_RAW, packet_snd() can save a larger value in reserve and later\nallocate headroom using a smaller value. Moving skb->data back by reserve\nthen places it before skb->head, and the following copy from userspace can\nattempt an out-of-bounds write.\n\npacket_sendmsg_spkt() has the same issue because it calculates its\nreservation and header offset from separate reads before dropping the RCU\nread lock to allocate the skb.\n\nAdd LL_RESERVED_SPACE_EX() for callers that already saved a header length.\nRead hard_header_len once in packet_snd() and use it for allocation and\nconstruction. In packet_sendmsg_spkt(), preserve the allocation-time value\nthrough the device lookup retry.\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":"2026-08-21 17:16:44","updated_at":"2026-08-21 17:16:44"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/03390aa32e669cc4ecd7d34108e2e1afc13d689d","name":"https://git.kernel.org/stable/c/03390aa32e669cc4ecd7d34108e2e1afc13d689d","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/9052756290962ffb9a661bcf319e92dedaaedfed","name":"https://git.kernel.org/stable/c/9052756290962ffb9a661bcf319e92dedaaedfed","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/b06b6fce6d7deaf7238e09b48ce3b1125ff41acd","name":"https://git.kernel.org/stable/c/b06b6fce6d7deaf7238e09b48ce3b1125ff41acd","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/5bb10753d428aadfc356a2bfe9acea09c82a62ec","name":"https://git.kernel.org/stable/c/5bb10753d428aadfc356a2bfe9acea09c82a62ec","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/91f041451f967cd87ed722a8f43c0b767a64f1a0","name":"https://git.kernel.org/stable/c/91f041451f967cd87ed722a8f43c0b767a64f1a0","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-74582","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-74582","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected b84bbaf7a6c8cca24f8acf25a2c8e46913a947ba 91f041451f967cd87ed722a8f43c0b767a64f1a0 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected b84bbaf7a6c8cca24f8acf25a2c8e46913a947ba 9052756290962ffb9a661bcf319e92dedaaedfed git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected b84bbaf7a6c8cca24f8acf25a2c8e46913a947ba 5bb10753d428aadfc356a2bfe9acea09c82a62ec git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected b84bbaf7a6c8cca24f8acf25a2c8e46913a947ba b06b6fce6d7deaf7238e09b48ce3b1125ff41acd git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected b84bbaf7a6c8cca24f8acf25a2c8e46913a947ba 03390aa32e669cc4ecd7d34108e2e1afc13d689d git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected d9fb8cc230b2a4757e9fe4f81468f81212d4deaa git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6190cce26e40bf71c4d375b21eea74bb07b6a0f3 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 01a658c1b9d4b5393c38d5a92d9112ab1425382a git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 8809ae6747e760e6f1d2453ceb08c9bcc4939766 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 4.4.133 4.5 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 4.9.103 4.10 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 4.14.44 4.15 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 4.16.12 4.17 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 4.17","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 4.17 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":["include/linux/netdevice.h","net/packet/af_packet.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"91f041451f967cd87ed722a8f43c0b767a64f1a0","status":"affected","version":"b84bbaf7a6c8cca24f8acf25a2c8e46913a947ba","versionType":"git"},{"lessThan":"9052756290962ffb9a661bcf319e92dedaaedfed","status":"affected","version":"b84bbaf7a6c8cca24f8acf25a2c8e46913a947ba","versionType":"git"},{"lessThan":"5bb10753d428aadfc356a2bfe9acea09c82a62ec","status":"affected","version":"b84bbaf7a6c8cca24f8acf25a2c8e46913a947ba","versionType":"git"},{"lessThan":"b06b6fce6d7deaf7238e09b48ce3b1125ff41acd","status":"affected","version":"b84bbaf7a6c8cca24f8acf25a2c8e46913a947ba","versionType":"git"},{"lessThan":"03390aa32e669cc4ecd7d34108e2e1afc13d689d","status":"affected","version":"b84bbaf7a6c8cca24f8acf25a2c8e46913a947ba","versionType":"git"},{"status":"affected","version":"d9fb8cc230b2a4757e9fe4f81468f81212d4deaa","versionType":"git"},{"status":"affected","version":"6190cce26e40bf71c4d375b21eea74bb07b6a0f3","versionType":"git"},{"status":"affected","version":"01a658c1b9d4b5393c38d5a92d9112ab1425382a","versionType":"git"},{"status":"affected","version":"8809ae6747e760e6f1d2453ceb08c9bcc4939766","versionType":"git"},{"lessThan":"4.5","status":"affected","version":"4.4.133","versionType":"semver"},{"lessThan":"4.10","status":"affected","version":"4.9.103","versionType":"semver"},{"lessThan":"4.15","status":"affected","version":"4.14.44","versionType":"semver"},{"lessThan":"4.17","status":"affected","version":"4.16.12","versionType":"semver"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["include/linux/netdevice.h","net/packet/af_packet.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"4.17"},{"lessThan":"4.17","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":"4.17","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.104","versionStartIncluding":"4.17","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.45","versionStartIncluding":"4.17","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.1.9","versionStartIncluding":"4.17","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2","versionStartIncluding":"4.17","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.4.133","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.9.103","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.14.44","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.16.12","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 non-ring send paths\n\npacket_snd() reads dev->hard_header_len multiple times while allocating\nand constructing an skb. Device reconfiguration can change this value\nconcurrently, for example through bonding device type changes.\n\nFor SOCK_RAW, packet_snd() can save a larger value in reserve and later\nallocate headroom using a smaller value. Moving skb->data back by reserve\nthen places it before skb->head, and the following copy from userspace can\nattempt an out-of-bounds write.\n\npacket_sendmsg_spkt() has the same issue because it calculates its\nreservation and header offset from separate reads before dropping the RCU\nread lock to allocate the skb.\n\nAdd LL_RESERVED_SPACE_EX() for callers that already saved a header length.\nRead hard_header_len once in packet_snd() and use it for allocation and\nconstruction. In packet_sendmsg_spkt(), preserve the allocation-time value\nthrough the device lookup retry.\n\nThe separate SOCK_DGRAM consistency problem between hard_header_len and\nheader_ops->create is not addressed here."}],"providerMetadata":{"dateUpdated":"2026-08-21T16:31:55.283Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/91f041451f967cd87ed722a8f43c0b767a64f1a0"},{"url":"https://git.kernel.org/stable/c/9052756290962ffb9a661bcf319e92dedaaedfed"},{"url":"https://git.kernel.org/stable/c/5bb10753d428aadfc356a2bfe9acea09c82a62ec"},{"url":"https://git.kernel.org/stable/c/b06b6fce6d7deaf7238e09b48ce3b1125ff41acd"},{"url":"https://git.kernel.org/stable/c/03390aa32e669cc4ecd7d34108e2e1afc13d689d"}],"title":"packet: use consistent hard_header_len in non-ring send paths","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-74582","datePublished":"2026-08-21T16:31:55.283Z","dateReserved":"2026-08-15T05:44:03.918Z","dateUpdated":"2026-08-21T16:31:55.283Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-08-21 17:16:44","lastModifiedDate":"2026-08-21 17:16:44","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"74582","Ordinal":"1","Title":"packet: use consistent hard_header_len in non-ring send paths","CVE":"CVE-2026-74582","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"74582","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\npacket: use consistent hard_header_len in non-ring send paths\n\npacket_snd() reads dev->hard_header_len multiple times while allocating\nand constructing an skb. Device reconfiguration can change this value\nconcurrently, for example through bonding device type changes.\n\nFor SOCK_RAW, packet_snd() can save a larger value in reserve and later\nallocate headroom using a smaller value. Moving skb->data back by reserve\nthen places it before skb->head, and the following copy from userspace can\nattempt an out-of-bounds write.\n\npacket_sendmsg_spkt() has the same issue because it calculates its\nreservation and header offset from separate reads before dropping the RCU\nread lock to allocate the skb.\n\nAdd LL_RESERVED_SPACE_EX() for callers that already saved a header length.\nRead hard_header_len once in packet_snd() and use it for allocation and\nconstruction. In packet_sendmsg_spkt(), preserve the allocation-time value\nthrough the device lookup retry.\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 non-ring send paths"}]}}}