CVE-2026-98132
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: bpf: don't downgrade half-dead scalar zero spills to STACK_ZERO states.c:__clean_func_state() can downgrade scalar zero spill to STACK_ZERO in the following case: *(u64 *)(r10 - 8) = 0; ... checkpoint ... r1 = *(u32 *)(r10 - 4); ... no reads from r10-8 ... Here 4 bytes at r10-8 are dead and verifier changes scalar spill to a combination: 0000pppp (p stands for poison). Such a change breaks precision propagation chains. All places that produce STACK_ZERO should call bpf_mark_chain_precision() for the zero source. This patch fixes the bug in a simplest way possible: avoids converting stack spills of zero to STACK_ZERO. Two smarter approaches are possible: - do bpf_mark_chain_precision() from __clean_func_state() - check slot liveness information in check_stack_write_fixed_off() I investigated both and the changes required are a bit tricky, hence go with a simple fix for the time being.
View original CVE JSON
{
"id": "CVE-2026-98132",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2026-09-25T11:17:44.603",
"lastModified": "2026-10-19T10:18:12.373",
"vulnStatus": "Analyzed",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: don't downgrade half-dead scalar zero spills to STACK_ZERO\n\nstates.c:__clean_func_state() can downgrade scalar zero spill to\nSTACK_ZERO in the following case:\n\n *(u64 *)(r10 - 8) = 0;\n ... checkpoint ...\n r1 = *(u32 *)(r10 - 4);\n ... no reads from r10-8 ...\n\nHere 4 bytes at r10-8 are dead and verifier changes scalar spill to a\ncombination: 0000pppp (p stands for poison). Such a change breaks\nprecision propagation chains. All places that produce STACK_ZERO\nshould call bpf_mark_chain_precision() for the zero source.\n\nThis patch fixes the bug in a simplest way possible:\navoids converting stack spills of zero to STACK_ZERO.\nTwo smarter approaches are possible:\n- do bpf_mark_chain_precision() from __clean_func_state()\n- check slot liveness information in check_stack_write_fixed_off()\n\nI investigated both and the changes required are a bit tricky,\nhence go with a simple fix for the time being."
}
],
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "unaffected",
"programFiles": [
"kernel/bpf/states.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "be23266b4a08540aa43d8503a2ea10247c8daebe",
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"versionType": "git",
"status": "affected"
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"status": "affected"
}
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{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "affected",
"programFiles": [
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],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "7.1",
"status": "affected"
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{
"version": "0",
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{
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"versionType": "semver",
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},
{
"version": "7.3",
"lessThanOrEqual": "*",
"versionType": "original_commit_for_fix",
"status": "unaffected"
}
]
}
]
}
],
"metrics": {
"cvssMetricV31": [
{
"source": "[email protected]",
"type": "Primary",
"cvssData": {
"version": "3.1",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
"baseScore": 5.5,
"baseSeverity": "MEDIUM",
"attackVector": "LOCAL",
"attackComplexity": "LOW",
"privilegesRequired": "LOW",
"userInteraction": "NONE",
"scope": "UNCHANGED",
"confidentialityImpact": "NONE",
"integrityImpact": "NONE",
"availabilityImpact": "HIGH"
},
"exploitabilityScore": 1.8,
"impactScore": 3.6
}
]
},
"weaknesses": [
{
"source": "[email protected]",
"type": "Primary",
"description": [
{
"lang": "en",
"value": "NVD-CWE-noinfo"
}
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"configurations": [
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"references": [
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"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
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}