{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-64414","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-07-19T15:36:31.786Z","datePublished":"2026-07-25T08:50:54.495Z","dateUpdated":"2026-08-17T04:55:13.439Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-08-17T04:55:13.439Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: handle unreadable frags\n\nsashiko reports:\n When an skb with unreadable fragments (such as from devmem TCP, where\n skb_frags_readable(skb) returns false) is processed by the u32 module,\n skb_copy_bits() will safely return a negative error code [..]\n\nxt_u32: bail out with hotdrop in this case.\ngather_frags: return -1, just as if we had no fragment header.\nnfnetlink_queue: restrict to the linear part.\nnfnetlink_log: restrict to the linear part.\n\nv2:\n - skb_zerocopy helpers don't copy readable flag, i.e. nfnetlink_queue\n is broken too\n xt_u32 shouldn't return true if hotdrop was set."}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","baseScore":7.5,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:N - Unreadable skbs arise on the receive side of device-memory TCP, and a remote peer can send packets that traverse netfilter hooks into u32, NFLOG, NFQUEUE, or IPv6 conntrack defragmentation. No local access is required in a network-exposed devmem TCP deployment.\nAC:L - Once devmem/header-split RX and an affected netfilter path are active, a sufficiently long payload or crafted IPv6 extension/fragment layout reliably reaches unreadable fragments. There is no race or condition the attacker must win, and triggering packets can be sent repeatedly.\nPR:N - The triggering packets are processed before application authentication, so the remote peer needs no account or kernel capability. CAP_NET_ADMIN is required for the operator's device and netfilter configuration, not for the attacker sending packets.\nUI:N - Packet reception and netfilter processing occur automatically without any victim action after the service and policy are configured.\nS:U - The resulting failure affects the same host kernel and does not cross a VM, IOMMU, or other distinct security authority boundary.\nC:N - skb_copy_bits() rejects the unreadable fragments before accessing their contents, while the NFQUEUE flag-loss path reaches an invalid page mapping. No attacker-accessible information-disclosure primitive was identified.\nI:N - The vulnerability causes BUG or invalid-access paths but provides no out-of-bounds write, use-after-free, type confusion, or attacker-controlled data modification.\nA:H - The u32, NFLOG, and IPv6 paths execute BUG(), and the NFQUEUE path can dereference an invalid page during netlink recvmsg. These can produce a kernel oops or panic and can be triggered repeatedly."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/ipv6/netfilter/nf_conntrack_reasm.c","net/netfilter/nfnetlink_log.c","net/netfilter/nfnetlink_queue.c","net/netfilter/xt_u32.c"],"versions":[{"version":"65249feb6b3df9e17bab5911ee56fa7b0971e231","lessThan":"3b13e7635795394705920cca1e1db7e4ca2e334b","status":"affected","versionType":"git"},{"version":"65249feb6b3df9e17bab5911ee56fa7b0971e231","lessThan":"fc5bfe63bacf8a3ae307b62b34206406ca733354","status":"affected","versionType":"git"},{"version":"65249feb6b3df9e17bab5911ee56fa7b0971e231","lessThan":"57056be3ec12e7d9ecd20a60d4060f510e4f284c","status":"affected","versionType":"git"},{"version":"65249feb6b3df9e17bab5911ee56fa7b0971e231","lessThan":"da5b58478a9c1b85608c9e40a3b8432d071b409e","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/ipv6/netfilter/nf_conntrack_reasm.c","net/netfilter/nfnetlink_log.c","net/netfilter/nfnetlink_queue.c","net/netfilter/xt_u32.c"],"versions":[{"version":"6.12","status":"affected"},{"version":"0","lessThan":"6.12","status":"unaffected","versionType":"semver"},{"version":"6.12.96","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.39","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.1.4","lessThanOrEqual":"7.1.*","status":"unaffected","versionType":"semver"},{"version":"7.2","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.12","versionEndExcluding":"6.12.96"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.12","versionEndExcluding":"6.18.39"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.12","versionEndExcluding":"7.1.4"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.12","versionEndExcluding":"7.2"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/3b13e7635795394705920cca1e1db7e4ca2e334b"},{"url":"https://git.kernel.org/stable/c/fc5bfe63bacf8a3ae307b62b34206406ca733354"},{"url":"https://git.kernel.org/stable/c/57056be3ec12e7d9ecd20a60d4060f510e4f284c"},{"url":"https://git.kernel.org/stable/c/da5b58478a9c1b85608c9e40a3b8432d071b409e"}],"title":"netfilter: handle unreadable frags","x_generator":{"engine":"bippy-1.2.0"}}}}