CVE-2026-98085
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: bpf: backtrack_insn(): Handle ld_{abs,ind} subprog exit edge Nicholas Carlini reported a bug in precision backtracking mechanism for BPF_LD | BPF_{IND,ABS} instructions. These instructions are modelled as two branches: - fallthrough; - implicit exit from current subprogram. The implicit exit case was not handled by the backtrack_insn() function. When backtracking such a path backtrack_insn() did not call bt_subprog_enter(), which meant that backtracking continued manipulating precision marks in a caller frame, while looking at instructions in a callee frame. This lead to segmentation faults during verification (see the selftest), or unsound state pruning.
Severity
Not scored
CVSS score
Not available
Vulnerability status
Undergoing Analysis
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-09-25 11:17:38.087000
Last modified
2026-10-21 13:21:22.137000
View original CVE JSON
{
"id": "CVE-2026-98085",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2026-09-25T11:17:38.087",
"lastModified": "2026-10-21T13:21:22.137",
"vulnStatus": "Undergoing Analysis",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: backtrack_insn(): Handle ld_{abs,ind} subprog exit edge\n\nNicholas Carlini reported a bug in precision backtracking mechanism\nfor BPF_LD | BPF_{IND,ABS} instructions. These instructions are\nmodelled as two branches:\n- fallthrough;\n- implicit exit from current subprogram.\n\nThe implicit exit case was not handled by the backtrack_insn()\nfunction. When backtracking such a path backtrack_insn() did not\ncall bt_subprog_enter(), which meant that backtracking continued\nmanipulating precision marks in a caller frame, while looking at\ninstructions in a callee frame.\n\nThis lead to segmentation faults during verification (see the\nselftest), or unsound state pruning."
}
],
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "unaffected",
"programFiles": [
"kernel/bpf/backtrack.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "37ad2bb11e9de92cb7b94548705eeedd87f7d392",
"lessThan": "19cca7c36055906b3cff3e297618ee8a50cde25d",
"versionType": "git",
"status": "affected"
},
{
"version": "8674e2db06cff6b50f2216eed9a761d15425bb34",
"lessThan": "12c064bcfa56e3631be9f5336ee113b7f849959a",
"versionType": "git",
"status": "affected"
},
{
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{
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{
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{
"version": "de1055e7f9e67af32b1f3376066272b04e5223c0",
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},
{
"version": "d846d83bdacbd8f14fc45c63b8c1d22608452e1c",
"versionType": "git",
"status": "affected"
},
{
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"lessThan": "6.6.160",
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"status": "affected"
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{
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"status": "affected"
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{
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"status": "affected"
},
{
"version": "5.10.265",
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},
{
"version": "5.15.216",
"lessThan": "5.16",
"versionType": "semver",
"status": "affected"
},
{
"version": "6.1.183",
"lessThan": "6.2",
"versionType": "semver",
"status": "affected"
},
{
"version": "7.0.10",
"lessThan": "7.1",
"versionType": "semver",
"status": "affected"
}
]
},
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "affected",
"programFiles": [
"kernel/bpf/backtrack.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "7.1",
"status": "affected"
},
{
"version": "0",
"lessThan": "7.1",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.6.160",
"lessThanOrEqual": "6.6.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.12.114",
"lessThanOrEqual": "6.12.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.18.57",
"lessThanOrEqual": "6.18.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "7.2.7",
"lessThanOrEqual": "7.2.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "7.3",
"lessThanOrEqual": "*",
"versionType": "original_commit_for_fix",
"status": "unaffected"
}
]
}
]
}
],
"metrics": {},
"references": [
{
"url": "https://git.kernel.org/stable/c/12c064bcfa56e3631be9f5336ee113b7f849959a",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
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"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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{
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"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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{
"url": "https://git.kernel.org/stable/c/671b7b9a660ef15b25faa3df161205b9dc8d1eb2",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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{
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}