UnratedFix available
xsk: Use a 32-bit compare in xsk_map_gen_lookup
Type: advisorySources: OSV
In the Linux kernel, the following vulnerability has been resolved: xsk: Use a 32-bit compare in xsk_map_gen_lookup xsk_map_gen_lookup() loads a u32 key and compares it with max_entries using BPF_JMP_IMM. BPF immediates are sign-extended to 64 bits, so a max_entries value of 0x80000000 or higher becomes a threshold larger than every zero-extended 32-bit key. An out-of-range index then skips the bounds check and the generated lookup reads past xsk_map[]. Compare with BPF_JMP32_IMM so the check stays in 32-bit unsigned range.
- Products
- Kernel
- Affected versions
- Not specified
- Fixed versions
- 5.10.271, 5.15.222, 6.1.189, 6.12.112, 6.18.55, 6.6.158, 7.2.9
- CVEs
- CVE-2026-98631
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 3 Nov 2026, 15:29 UTC · Revision 1
Source evidence
xsk: Use a 32-bit compare in xsk_map_gen_lookup
core-osv · Original sourcePublished 18 Oct 2026, 15:19 UTC
In the Linux kernel, the following vulnerability has been resolved: xsk: Use a 32-bit compare in xsk_map_gen_lookup xsk_map_gen_lookup() loads a u32 key and compares it with max_entries using BPF_JMP_IMM. BPF immediates are sign-extended to 64 bits, so a max_entries value of 0x80000000 or higher becomes a threshold larger than every zero-extended 32-bit key. An out-of-range index then skips the bounds check and the generated lookup reads past xsk_map[]. Compare with BPF_JMP32_IMM so the check stays in 32-bit unsigned range.
osv:CVE-2026-98631
Kernel
Fixed versions: 5.10.271, 5.15.222, 6.1.189, 6.6.158, 6.12.112, 6.18.55, 7.2.9
Complete source record
{
"id": "fc9c2f97e0ac29472da43a50a3175eced8689e4048feaafdee81daf777ce2b31",
"url": "https://osv.dev/vulnerability/CVE-2026-98631",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "xsk: Use a 32-bit compare in xsk_map_gen_lookup",
"summary": "In the Linux kernel, the following vulnerability has been resolved: xsk: Use a 32-bit compare in xsk_map_gen_lookup xsk_map_gen_lookup() loads a u32 key and compares it with max_entries using BPF_JMP_IMM. BPF immediates are sign-extended to 64 bits, so a max_entries value of 0x80000000 or higher becomes a threshold larger than every zero-extended 32-bit key. An out-of-range index then skips the bounds check and the generated lookup reads past xsk_map[]. Compare with BPF_JMP32_IMM so the check stays in 32-bit unsigned range.",
"evidence": "osv:CVE-2026-98631",
"products": [
{
"name": {
"value": "Kernel",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "5.10.271",
"evidence": "/affected/1/ranges"
},
{
"value": "5.15.222",
"evidence": "/affected/1/ranges"
},
{
"value": "6.1.189",
"evidence": "/affected/1/ranges"
},
{
"value": "6.6.158",
"evidence": "/affected/1/ranges"
},
{
"value": "6.12.112",
"evidence": "/affected/1/ranges"
},
{
"value": "6.18.55",
"evidence": "/affected/1/ranges"
},
{
"value": "7.2.9",
"evidence": "/affected/1/ranges"
}
],
"affected_versions": []
}
],
"severity": "unknown",
"structured": {
"id": "CVE-2026-98631",
"aliases": [
"CVE-2026-98631"
],
"affected": [
{
"ranges": [
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"type": "GIT",
"events": [
{
"introduced": "e65650f291ee72fc578d6346080fc4699204ef2c"
},
{
"fixed": "c6d5c582d55a8f229d75e98d62eaa065b0deb18d"
},
{
"fixed": "227ec890559e922e235eb543646e3bf0bd8269b0"
},
{
"fixed": "11d9be35c1f4233798e99be98bc474f83a254c6c"
},
{
"fixed": "123f90f394ca404ab8796a7c8072ff7fa5b65a9c"
},
{
"fixed": "36461e58f88a1b723f86693f437ac12e60ff4363"
},
{
"fixed": "b5c0cff0c5331582ab01c4c423731453a8381acc"
},
{
"fixed": "3c1e0a4bc156b8d5c5772dbc76b9ea74dce5ca24"
},
{
"fixed": "70504de0bb627848667207bec7ccfd647deb8814"
}
]
}
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98631.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "5.5.0"
},
{
"fixed": "5.10.271"
}
]
},
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "5.11.0"
},
{
"fixed": "5.15.222"
}
]
},
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "5.16.0"
},
{
"fixed": "6.1.189"
}
]
},
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "6.2.0"
},
{
"fixed": "6.6.158"
}
]
},
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "6.7.0"
},
{
"fixed": "6.12.112"
}
]
},
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "6.13.0"
},
{
"fixed": "6.18.55"
}
]
},
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "6.19.0"
},
{
"fixed": "7.2.9"
}
]
}
],
"package": {
"name": "Kernel",
"ecosystem": "Linux"
},
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98631.json"
}
}
],
"modified": "2026-10-28T02:30:29.901702554Z",
"provider": "osv",
"references": [
"https://git.kernel.org/stable/c/11d9be35c1f4233798e99be98bc474f83a254c6c",
"https://git.kernel.org/stable/c/123f90f394ca404ab8796a7c8072ff7fa5b65a9c",
"https://git.kernel.org/stable/c/227ec890559e922e235eb543646e3bf0bd8269b0",
"https://git.kernel.org/stable/c/36461e58f88a1b723f86693f437ac12e60ff4363",
"https://git.kernel.org/stable/c/3c1e0a4bc156b8d5c5772dbc76b9ea74dce5ca24",
"https://git.kernel.org/stable/c/70504de0bb627848667207bec7ccfd647deb8814",
"https://git.kernel.org/stable/c/b5c0cff0c5331582ab01c4c423731453a8381acc",
"https://git.kernel.org/stable/c/c6d5c582d55a8f229d75e98d62eaa065b0deb18d",
"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98631.json",
"https://nvd.nist.gov/vuln/detail/CVE-2026-98631",
"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
],
"provider_metadata": {
"cna_assigner": "Linux",
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98631.json"
}
},
"related_cves": [
{
"value": "CVE-2026-98631",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": null
},
"source_id": "core-osv",
"document_id": 496832,
"published_at": "2026-10-18T15:19:53.529+00:00"
}