GHSA-GP9V-9C23-FW32
Vulnerability from github – Published: 2026-08-15 06:32 – Updated: 2026-08-17 06:33In the Linux kernel, the following vulnerability has been resolved:
geneve: validate inner network offset in geneve_gro_complete()
Even with both paths gated on gs->gro_hint, geneve_gro_complete() re-derives the inner dispatch type and length from the packet and the current gs->gro_hint, independently of geneve_gro_receive(). The two can disagree if gs->gro_hint flips under a concurrent geneve_quiesce()/ geneve_unquiesce() (sk_user_data is NULL across a synchronize_net()), or if the re-read option bytes differ from the ones receive parsed.
geneve_gro_receive() already records the inner network header position in NAPI_GRO_CB()->inner_network_offset. Have geneve_gro_complete() compute the offset it is about to dispatch at, adding ETH_HLEN in the ETH_P_TEB case where eth_gro_complete() steps over the inner MAC header, and bail out if it lands past inner_network_offset.
Use a lower bound rather than exact equality: between gh_len and the inner L3 header, geneve_gro_receive() may also have pulled an inner VLAN tag (vlan_gro_receive() advances the recorded offset past it), which only moves inner_network_offset further out. A valid frame therefore always satisfies inner_nh <= inner_network_offset, while a gh_len inflated by a hint gro_receive() did not honour dispatches past the validated inner header, i.e. the out-of-bounds completion. Only the latter is rejected.
{
"affected": [],
"aliases": [
"CVE-2026-72407"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-08-15T06:22:14Z",
"severity": "CRITICAL"
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\ngeneve: validate inner network offset in geneve_gro_complete()\n\nEven with both paths gated on gs-\u003egro_hint, geneve_gro_complete()\nre-derives the inner dispatch type and length from the packet and the\ncurrent gs-\u003egro_hint, independently of geneve_gro_receive(). The two can\ndisagree if gs-\u003egro_hint flips under a concurrent geneve_quiesce()/\ngeneve_unquiesce() (sk_user_data is NULL across a synchronize_net()), or if\nthe re-read option bytes differ from the ones receive parsed.\n\ngeneve_gro_receive() already records the inner network header position in\nNAPI_GRO_CB()-\u003einner_network_offset. Have geneve_gro_complete() compute the\noffset it is about to dispatch at, adding ETH_HLEN in the ETH_P_TEB case\nwhere eth_gro_complete() steps over the inner MAC header, and bail out if\nit lands past inner_network_offset.\n\nUse a lower bound rather than exact equality: between gh_len and the inner\nL3 header, geneve_gro_receive() may also have pulled an inner VLAN tag\n(vlan_gro_receive() advances the recorded offset past it), which only moves\ninner_network_offset further out. A valid frame therefore always satisfies\ninner_nh \u003c= inner_network_offset, while a gh_len inflated by a hint\ngro_receive() did not honour dispatches past the validated inner header,\ni.e. the out-of-bounds completion. Only the latter is rejected.",
"id": "GHSA-gp9v-9c23-fw32",
"modified": "2026-08-17T06:33:28Z",
"published": "2026-08-15T06:32:23Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-72407"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/cbb0d30a1ad6fc9439b1dc9b4f5a7a9140d3b11f"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/e2087447f562692ff0cd08a0554d8d4ad083aa5c"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
Sightings
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Nomenclature
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- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.