CVE-2026-80590 (GCVE-0-2026-80590)
Vulnerability from cvelistv5
Published
2026-08-28 06:35
Modified
2026-10-19 08:43
Severity ?
8.6 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: inet: frags: strip GSO state from fragments before reassembly A virtio_net_hdr (tun/tap, or AF_PACKET with PACKET_VNET_HDR) can mark an IPv4 or IPv6 fragment as GSO; nothing relates gso_type to frag_off. inet_frag_reasm_prepare()/inet_frag_reasm_finish() keep the first fragment's skb as the head of the reassembled datagram, including its shinfo->gso_size/gso_type/gso_segs, and chain the remaining fragments on frag_list with whatever linear/paged layout they arrived with. After ip_defrag() (ip_local_deliver(), nf_defrag_ipv4, ...) the reassembled skb therefore still claims to be GSO (SKB_GSO_DODGY), and the next software segmentation point - udp_rcv_segment() on local delivery, validate_xmit_skb(), or the ip_finish_output_gso() slow path - hands it to skb_segment(). skb_segment()'s frag_list walk assumes GRO-shaped input and hits one of its BUG_ON()s. Two writes to a tap by an unprivileged user in its own userns are enough: kernel BUG at net/core/skbuff.c:4899! Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI CPU: 0 UID: 1000 PID: 82 Comm: poc Not tainted 7.2.0-pentest+ #2 RIP: 0010:skb_segment+0x20ca/0x48b0 Call Trace: <TASK> __udp_gso_segment+0x29a/0x27d0 udp4_ufo_fragment+0x458/0x6c0 inet_gso_segment+0x429/0x1340 skb_mac_gso_segment+0x233/0x4f0 __skb_gso_segment+0x308/0x660 udp_queue_rcv_skb+0x440/0xad0 udp_unicast_rcv_skb+0xc7/0x2c0 udp_rcv+0x16ce/0x2260 ip_protocol_deliver_rcu+0x197/0x2d0 ip_local_deliver+0x430/0x690 ip_rcv+0x16f/0x1f0 __netif_receive_skb_one_core+0x15e/0x1c0 __netif_receive_skb+0x1e/0x110 netif_receive_skb+0xf6/0x5c0 tun_rx_batched.isra.0+0x3ab/0x790 tun_get_user+0x17c3/0x3550 tun_chr_write_iter+0xba/0x1b0 vfs_write+0x646/0x1130 </TASK> Kernel panic - not syncing: Fatal exception in interrupt This runs with BH disabled, so it is a panic rather than an oops. The same is reachable with CAP_NET_RAW in a netns where a defrag point precedes a GSO point, and from a guest whose VMM forwards virtio_net_hdr to a tap. The SKB_GSO_DODGY frag_list checks added by commit 3dcbdb134f32 ("net: gso: Fix skb_segment splat when splitting gso_size mangled skb having linear-headed frag_list") and by commit 9e4b7a99a03a ("net: gso: fix panic on frag_list with mixed head alloc types") do not cover it: page-backed heads skip them, and kmalloc heads skip them when gso_size == skb_headlen(head), which the sender controls. An skb entering a frag queue is an IP fragment by definition and cannot legitimately carry GSO state: GRO does not merge fragments and the stack segments before it fragments, so only untrusted sources are affected. This has been reachable since commit f43798c27684 ("tun: Allow GSO using virtio_net_hdr"), the first path that let userspace attach GSO metadata to an IP fragment. Reset the GSO fields of every fragment as it is queued, in inet_frag_queue_insert(), which IPv4, IPv6, nf_conntrack_reasm and 6lowpan reassembly share; then neither the head nor the frag_list members of the reassembled skb carry them (the members matter too: the ip_do_fragment()/ip6_fragment() fast paths send them out as they are). The head may remain CHECKSUM_PARTIAL; that is already accepted on receive and resolved by skb_checksum_help() in ip_do_fragment()/ip6_fragment() on forward. Tested on top of net.git (dc4b95b8fee9), x86_64: the tap reproducer above, two further IPv4 frag_list geometries that reach BUG_ON(i >= nfrags) and BUG_ON(!list_skb->head_frag), and an IPv6 fragment-header variant (udp6_ufo_fragment()) each panic the unpatched kernel; with this patch all four datagrams are delivered intact and nothing is logged.
References
Impacted products
Vendor Product Version
Linux Linux Version: f43798c27684ab925adde7d8acc34c78c6e50df8
Version: f43798c27684ab925adde7d8acc34c78c6e50df8
Version: f43798c27684ab925adde7d8acc34c78c6e50df8
Version: f43798c27684ab925adde7d8acc34c78c6e50df8
Version: f43798c27684ab925adde7d8acc34c78c6e50df8
Version: f43798c27684ab925adde7d8acc34c78c6e50df8
Version: f43798c27684ab925adde7d8acc34c78c6e50df8
Version: f43798c27684ab925adde7d8acc34c78c6e50df8
Version: f43798c27684ab925adde7d8acc34c78c6e50df8
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          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ninet: frags: strip GSO state from fragments before reassembly\n\nA virtio_net_hdr (tun/tap, or AF_PACKET with PACKET_VNET_HDR) can mark\nan IPv4 or IPv6 fragment as GSO; nothing relates gso_type to frag_off.\ninet_frag_reasm_prepare()/inet_frag_reasm_finish() keep the first\nfragment\u0027s skb as the head of the reassembled datagram, including its\nshinfo-\u003egso_size/gso_type/gso_segs, and chain the remaining fragments\non frag_list with whatever linear/paged layout they arrived with.\n\nAfter ip_defrag() (ip_local_deliver(), nf_defrag_ipv4, ...) the\nreassembled skb therefore still claims to be GSO (SKB_GSO_DODGY), and\nthe next software segmentation point - udp_rcv_segment() on local\ndelivery, validate_xmit_skb(), or the ip_finish_output_gso() slow\npath - hands it to skb_segment(). skb_segment()\u0027s frag_list walk\nassumes GRO-shaped input and hits one of its BUG_ON()s. Two writes to\na tap by an unprivileged user in its own userns are enough:\n\n  kernel BUG at net/core/skbuff.c:4899!\n  Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI\n  CPU: 0 UID: 1000 PID: 82 Comm: poc Not tainted 7.2.0-pentest+ #2\n  RIP: 0010:skb_segment+0x20ca/0x48b0\n  Call Trace:\n   \u003cTASK\u003e\n   __udp_gso_segment+0x29a/0x27d0\n   udp4_ufo_fragment+0x458/0x6c0\n   inet_gso_segment+0x429/0x1340\n   skb_mac_gso_segment+0x233/0x4f0\n   __skb_gso_segment+0x308/0x660\n   udp_queue_rcv_skb+0x440/0xad0\n   udp_unicast_rcv_skb+0xc7/0x2c0\n   udp_rcv+0x16ce/0x2260\n   ip_protocol_deliver_rcu+0x197/0x2d0\n   ip_local_deliver+0x430/0x690\n   ip_rcv+0x16f/0x1f0\n   __netif_receive_skb_one_core+0x15e/0x1c0\n   __netif_receive_skb+0x1e/0x110\n   netif_receive_skb+0xf6/0x5c0\n   tun_rx_batched.isra.0+0x3ab/0x790\n   tun_get_user+0x17c3/0x3550\n   tun_chr_write_iter+0xba/0x1b0\n   vfs_write+0x646/0x1130\n   \u003c/TASK\u003e\n  Kernel panic - not syncing: Fatal exception in interrupt\n\nThis runs with BH disabled, so it is a panic rather than an oops. The\nsame is reachable with CAP_NET_RAW in a netns where a defrag point\nprecedes a GSO point, and from a guest whose VMM forwards\nvirtio_net_hdr to a tap. The SKB_GSO_DODGY frag_list checks added by\ncommit 3dcbdb134f32 (\"net: gso: Fix skb_segment splat when splitting\ngso_size mangled skb having linear-headed frag_list\") and by\ncommit 9e4b7a99a03a (\"net: gso: fix panic on frag_list with mixed head\nalloc types\") do not cover it: page-backed heads skip them, and kmalloc\nheads skip them when gso_size == skb_headlen(head), which the sender\ncontrols.\n\nAn skb entering a frag queue is an IP fragment by definition and\ncannot legitimately carry GSO state: GRO does not merge fragments and\nthe stack segments before it fragments, so only untrusted sources are\naffected. This has been reachable since\ncommit f43798c27684 (\"tun: Allow GSO using virtio_net_hdr\"), the first\npath that let userspace attach GSO metadata to an IP fragment. Reset\nthe GSO fields of every fragment as it is queued, in\ninet_frag_queue_insert(), which IPv4, IPv6, nf_conntrack_reasm and\n6lowpan reassembly share; then neither the head nor the frag_list\nmembers of the reassembled skb carry them (the members matter too:\nthe ip_do_fragment()/ip6_fragment() fast paths send them out as they\nare). The head may remain CHECKSUM_PARTIAL; that is already accepted\non receive and resolved by skb_checksum_help() in\nip_do_fragment()/ip6_fragment() on forward.\n\nTested on top of net.git (dc4b95b8fee9), x86_64: the tap reproducer\nabove, two further IPv4 frag_list geometries that reach\nBUG_ON(i \u003e= nfrags) and BUG_ON(!list_skb-\u003ehead_frag), and an IPv6\nfragment-header variant (udp6_ufo_fragment()) each panic the unpatched\nkernel; with this patch all four datagrams are delivered intact and\nnothing is logged."
        }
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            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H",
            "version": "3.1"
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              "lang": "en",
              "value": "AV:N - A malicious cloud VM guest injects virtio_net_hdr-marked IPv4/IPv6 fragments through virtio-net/vhost-tap into the host ip_rcv() path; the same inet_frag reassembly and skb_segment() crash also fires on validate_xmit_skb()/ip_finish_output_gso() when such skbs traverse forwarding.\nAC:L - The attacker fully controls virtio_net_hdr gso_type/gso_size and fragment geometry; the commit reproduces a host panic from two tap writes with no races, timing, or uncontrollable memory layout required.\nPR:N - On typical KVM/QEMU tap-backed virtio-net deployments a tenant VM needs no host account or capability; exploitation uses only the pre-provisioned virtual NIC, not init-namespace root or CAP_NET_ADMIN on the host.\nUI:N - Packet injection, ip_defrag reassembly, and GSO segmentation run automatically in softirq once crafted virtio fragments are sent; no victim mount, click, or other cooperative action is required.\nS:C - A guest VM tenant can panic the host kernel by crossing the hypervisor virtio/tap boundary, impacting resources outside the guest security authority even though the demonstrated primitive is denial of service rather than full escape.\nC:N - Impact is an intentional BUG_ON in skb_segment() frag_list handling; there is no demonstrated out-of-bounds read, use-after-free, or other information-disclosure primitive before the assertion aborts.\nI:N - The failure aborts in skb_segment() before any out-of-bounds write, page-desc conversion, or control-flow hijack; attacker-controlled metadata only reaches a defensive assertion, not a memory modification primitive.\nA:H - Triggering skb_segment() BUG_ON from tun_rx/tun_get_user runs with BH disabled and causes a fatal kernel panic, fully and repeatedly denying availability of the affected host until reboot."
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      "title": "inet: frags: strip GSO state from fragments before reassembly",
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    "assignerShortName": "Linux",
    "cveId": "CVE-2026-80590",
    "datePublished": "2026-08-28T06:35:12.516Z",
    "dateReserved": "2026-08-26T14:34:25.770Z",
    "dateUpdated": "2026-10-19T08:43:12.426Z",
    "state": "PUBLISHED"
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      "containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-80590\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"yes\"}, {\"Technical Impact\": \"partial\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-10-16T19:18:13.413771Z\"}}}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-10-16T19:18:14.027Z\"}}], \"cna\": {\"title\": \"inet: frags: strip GSO state from fragments before reassembly\", \"metrics\": [{\"cvssV3_1\": {\"version\": \"3.1\", \"baseScore\": 8.6, \"baseSeverity\": \"HIGH\", \"vectorString\": \"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H\"}, \"scenarios\": [{\"lang\": \"en\", \"value\": \"AV:N - A malicious cloud VM guest injects virtio_net_hdr-marked IPv4/IPv6 fragments through virtio-net/vhost-tap into the host ip_rcv() path; the same inet_frag reassembly and skb_segment() crash also fires on validate_xmit_skb()/ip_finish_output_gso() when such skbs traverse forwarding.\\nAC:L - The attacker fully controls virtio_net_hdr gso_type/gso_size and fragment geometry; the commit reproduces a host panic from two tap writes with no races, timing, or uncontrollable memory layout required.\\nPR:N - On typical KVM/QEMU tap-backed virtio-net deployments a tenant VM needs no host account or capability; exploitation uses only the pre-provisioned virtual NIC, not init-namespace root or CAP_NET_ADMIN on the host.\\nUI:N - Packet injection, ip_defrag reassembly, and GSO segmentation run automatically in softirq once crafted virtio fragments are sent; no victim mount, click, or other cooperative action is required.\\nS:C - A guest VM tenant can panic the host kernel by crossing the hypervisor virtio/tap boundary, impacting resources outside the guest security authority even though the demonstrated primitive is denial of service rather than full escape.\\nC:N - Impact is an intentional BUG_ON in skb_segment() frag_list handling; there is no demonstrated out-of-bounds read, use-after-free, or other information-disclosure primitive before the assertion aborts.\\nI:N - The failure aborts in skb_segment() before any out-of-bounds write, page-desc conversion, or control-flow hijack; attacker-controlled metadata only reaches a defensive assertion, not a memory modification primitive.\\nA:H - Triggering skb_segment() BUG_ON from tun_rx/tun_get_user runs with BH disabled and causes a fatal kernel panic, fully and repeatedly denying availability of the affected host until reboot.\"}]}], \"affected\": [{\"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\", \"vendor\": \"Linux\", \"product\": \"Linux\", \"versions\": [{\"status\": \"affected\", \"version\": \"f43798c27684ab925adde7d8acc34c78c6e50df8\", \"lessThan\": \"cfdbc8c2e6f9ef5d8b8e54859da03dfe682b0bee\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"f43798c27684ab925adde7d8acc34c78c6e50df8\", \"lessThan\": \"29dda278a5ed272f2230ff4eaa23cf403107bba0\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"f43798c27684ab925adde7d8acc34c78c6e50df8\", \"lessThan\": \"14a8f3e10fa9a5abd6cedcdaa0c0b7ea9a09f234\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"f43798c27684ab925adde7d8acc34c78c6e50df8\", \"lessThan\": \"3edf721bb4b99d272c336631b44e3d8ff9a4f31b\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"f43798c27684ab925adde7d8acc34c78c6e50df8\", \"lessThan\": \"dec2edb7aaf12a8878b3a03172ea8fc277b8eaad\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"f43798c27684ab925adde7d8acc34c78c6e50df8\", \"lessThan\": \"c49f04e8d2b94dbb8d9fd99731dd3f00589c8ace\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"f43798c27684ab925adde7d8acc34c78c6e50df8\", \"lessThan\": \"69b73b74d9eb45f5560a8fe4fa406ada580e1340\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"f43798c27684ab925adde7d8acc34c78c6e50df8\", \"lessThan\": \"da857e448322a2e871ce3ecc2900027041160d43\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"f43798c27684ab925adde7d8acc34c78c6e50df8\", \"lessThan\": \"d5dc1e69fd7258ea605c9952e5d5947539159ae3\", \"versionType\": \"git\"}], \"programFiles\": [\"net/ipv4/inet_fragment.c\"], \"defaultStatus\": \"unaffected\"}, {\"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\", \"vendor\": \"Linux\", \"product\": \"Linux\", \"versions\": [{\"status\": \"affected\", \"version\": \"2.6.27\"}, {\"status\": \"unaffected\", \"version\": \"0\", \"lessThan\": \"2.6.27\", \"versionType\": \"semver\"}, {\"status\": \"unaffected\", \"version\": \"5.10.268\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"5.10.*\"}, {\"status\": \"unaffected\", \"version\": \"5.15.219\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"5.15.*\"}, {\"status\": \"unaffected\", \"version\": \"6.1.186\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"6.1.*\"}, {\"status\": \"unaffected\", \"version\": \"6.6.155\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"6.6.*\"}, {\"status\": \"unaffected\", \"version\": \"6.12.107\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"6.12.*\"}, {\"status\": \"unaffected\", \"version\": \"6.18.48\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"6.18.*\"}, {\"status\": \"unaffected\", \"version\": \"7.1.12\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"7.1.*\"}, {\"status\": \"unaffected\", \"version\": \"7.2.2\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"7.2.*\"}, {\"status\": \"unaffected\", \"version\": \"7.3\", \"versionType\": \"original_commit_for_fix\", \"lessThanOrEqual\": \"*\"}], \"programFiles\": [\"net/ipv4/inet_fragment.c\"], \"defaultStatus\": \"affected\"}], \"references\": [{\"url\": \"https://git.kernel.org/stable/c/cfdbc8c2e6f9ef5d8b8e54859da03dfe682b0bee\"}, {\"url\": \"https://git.kernel.org/stable/c/29dda278a5ed272f2230ff4eaa23cf403107bba0\"}, {\"url\": \"https://git.kernel.org/stable/c/14a8f3e10fa9a5abd6cedcdaa0c0b7ea9a09f234\"}, {\"url\": \"https://git.kernel.org/stable/c/3edf721bb4b99d272c336631b44e3d8ff9a4f31b\"}, {\"url\": \"https://git.kernel.org/stable/c/dec2edb7aaf12a8878b3a03172ea8fc277b8eaad\"}, {\"url\": \"https://git.kernel.org/stable/c/c49f04e8d2b94dbb8d9fd99731dd3f00589c8ace\"}, {\"url\": \"https://git.kernel.org/stable/c/69b73b74d9eb45f5560a8fe4fa406ada580e1340\"}, {\"url\": \"https://git.kernel.org/stable/c/da857e448322a2e871ce3ecc2900027041160d43\"}, {\"url\": \"https://git.kernel.org/stable/c/d5dc1e69fd7258ea605c9952e5d5947539159ae3\"}], \"x_generator\": {\"engine\": \"bippy-1.2.0\"}, \"descriptions\": [{\"lang\": \"en\", \"value\": \"In the Linux kernel, the following vulnerability has been resolved:\\n\\ninet: frags: strip GSO state from fragments before reassembly\\n\\nA virtio_net_hdr (tun/tap, or AF_PACKET with PACKET_VNET_HDR) can mark\\nan IPv4 or IPv6 fragment as GSO; nothing relates gso_type to frag_off.\\ninet_frag_reasm_prepare()/inet_frag_reasm_finish() keep the first\\nfragment\u0027s skb as the head of the reassembled datagram, including its\\nshinfo-\u003egso_size/gso_type/gso_segs, and chain the remaining fragments\\non frag_list with whatever linear/paged layout they arrived with.\\n\\nAfter ip_defrag() (ip_local_deliver(), nf_defrag_ipv4, ...) the\\nreassembled skb therefore still claims to be GSO (SKB_GSO_DODGY), and\\nthe next software segmentation point - udp_rcv_segment() on local\\ndelivery, validate_xmit_skb(), or the ip_finish_output_gso() slow\\npath - hands it to skb_segment(). skb_segment()\u0027s frag_list walk\\nassumes GRO-shaped input and hits one of its BUG_ON()s. Two writes to\\na tap by an unprivileged user in its own userns are enough:\\n\\n  kernel BUG at net/core/skbuff.c:4899!\\n  Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI\\n  CPU: 0 UID: 1000 PID: 82 Comm: poc Not tainted 7.2.0-pentest+ #2\\n  RIP: 0010:skb_segment+0x20ca/0x48b0\\n  Call Trace:\\n   \u003cTASK\u003e\\n   __udp_gso_segment+0x29a/0x27d0\\n   udp4_ufo_fragment+0x458/0x6c0\\n   inet_gso_segment+0x429/0x1340\\n   skb_mac_gso_segment+0x233/0x4f0\\n   __skb_gso_segment+0x308/0x660\\n   udp_queue_rcv_skb+0x440/0xad0\\n   udp_unicast_rcv_skb+0xc7/0x2c0\\n   udp_rcv+0x16ce/0x2260\\n   ip_protocol_deliver_rcu+0x197/0x2d0\\n   ip_local_deliver+0x430/0x690\\n   ip_rcv+0x16f/0x1f0\\n   __netif_receive_skb_one_core+0x15e/0x1c0\\n   __netif_receive_skb+0x1e/0x110\\n   netif_receive_skb+0xf6/0x5c0\\n   tun_rx_batched.isra.0+0x3ab/0x790\\n   tun_get_user+0x17c3/0x3550\\n   tun_chr_write_iter+0xba/0x1b0\\n   vfs_write+0x646/0x1130\\n   \u003c/TASK\u003e\\n  Kernel panic - not syncing: Fatal exception in interrupt\\n\\nThis runs with BH disabled, so it is a panic rather than an oops. The\\nsame is reachable with CAP_NET_RAW in a netns where a defrag point\\nprecedes a GSO point, and from a guest whose VMM forwards\\nvirtio_net_hdr to a tap. The SKB_GSO_DODGY frag_list checks added by\\ncommit 3dcbdb134f32 (\\\"net: gso: Fix skb_segment splat when splitting\\ngso_size mangled skb having linear-headed frag_list\\\") and by\\ncommit 9e4b7a99a03a (\\\"net: gso: fix panic on frag_list with mixed head\\nalloc types\\\") do not cover it: page-backed heads skip them, and kmalloc\\nheads skip them when gso_size == skb_headlen(head), which the sender\\ncontrols.\\n\\nAn skb entering a frag queue is an IP fragment by definition and\\ncannot legitimately carry GSO state: GRO does not merge fragments and\\nthe stack segments before it fragments, so only untrusted sources are\\naffected. This has been reachable since\\ncommit f43798c27684 (\\\"tun: Allow GSO using virtio_net_hdr\\\"), the first\\npath that let userspace attach GSO metadata to an IP fragment. Reset\\nthe GSO fields of every fragment as it is queued, in\\ninet_frag_queue_insert(), which IPv4, IPv6, nf_conntrack_reasm and\\n6lowpan reassembly share; then neither the head nor the frag_list\\nmembers of the reassembled skb carry them (the members matter too:\\nthe ip_do_fragment()/ip6_fragment() fast paths send them out as they\\nare). The head may remain CHECKSUM_PARTIAL; that is already accepted\\non receive and resolved by skb_checksum_help() in\\nip_do_fragment()/ip6_fragment() on forward.\\n\\nTested on top of net.git (dc4b95b8fee9), x86_64: the tap reproducer\\nabove, two further IPv4 frag_list geometries that reach\\nBUG_ON(i \u003e= nfrags) and BUG_ON(!list_skb-\u003ehead_frag), and an IPv6\\nfragment-header variant (udp6_ufo_fragment()) each panic the unpatched\\nkernel; with this patch all four datagrams are delivered intact and\\nnothing is logged.\"}], \"cpeApplicability\": [{\"nodes\": [{\"negate\": false, \"cpeMatch\": [{\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"5.10.268\", \"versionStartIncluding\": \"2.6.27\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"5.15.219\", \"versionStartIncluding\": \"2.6.27\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.1.186\", \"versionStartIncluding\": \"2.6.27\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.6.155\", \"versionStartIncluding\": \"2.6.27\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.12.107\", \"versionStartIncluding\": \"2.6.27\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.18.48\", \"versionStartIncluding\": \"2.6.27\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"7.1.12\", \"versionStartIncluding\": \"2.6.27\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"7.2.2\", \"versionStartIncluding\": \"2.6.27\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"7.3\", \"versionStartIncluding\": \"2.6.27\"}], \"operator\": \"OR\"}]}], \"providerMetadata\": {\"orgId\": \"416baaa9-dc9f-4396-8d5f-8c081fb06d67\", \"shortName\": \"Linux\", \"dateUpdated\": \"2026-10-19T08:43:12.426Z\"}}}",
      "cveMetadata": "{\"cveId\": \"CVE-2026-80590\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-10-19T08:43:12.426Z\", \"dateReserved\": \"2026-08-26T14:34:25.770Z\", \"assignerOrgId\": \"416baaa9-dc9f-4396-8d5f-8c081fb06d67\", \"datePublished\": \"2026-08-28T06:35:12.516Z\", \"assignerShortName\": \"Linux\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}


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