CVE-2026-99999
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: ipv4: validate checksum_start before completing checksum If a packet with bad checksum metadata gets into the ipv4 stack, skb_checksum_help can corrupt the network header and cause a bunch of mischief. This was discovered and reported by Paulos, and has been reporoduced by others independently since. We really shouldn't allow such packets in, but as a defence in depth measure, let's also check before we complete the checksum. A more complete validation at input is forthcoming, but needs more work.
Severity
CRITICAL
CVSS score
9.3
(v3.1)
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-10-15 13:17:14.137000
Last modified
2026-10-19 22:17:28.667000
View original CVE JSON
{
"id": "CVE-2026-99999",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2026-10-15T13:17:14.137",
"lastModified": "2026-10-19T22:17:28.667",
"vulnStatus": "Received",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nipv4: validate checksum_start before completing checksum\n\nIf a packet with bad checksum metadata gets into the ipv4 stack,\nskb_checksum_help can corrupt the network header and cause a bunch of\nmischief.\n\nThis was discovered and reported by Paulos, and has been reporoduced\nby others independently since.\n\nWe really shouldn't allow such packets in, but as a defence\nin depth measure, let's also check before we complete the checksum.\n\nA more complete validation at input is forthcoming, but needs more work."
}
],
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "unaffected",
"programFiles": [
"include/net/ip.h",
"net/bridge/netfilter/nf_conntrack_bridge.c",
"net/ipv4/ip_output.c",
"net/netfilter/nfnetlink_queue.c",
"net/netfilter/xt_CHECKSUM.c",
"net/xfrm/xfrm_output.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "f43798c27684ab925adde7d8acc34c78c6e50df8",
"lessThan": "a464d950f31c89565cbaae038cc60db04fe01956",
"versionType": "git",
"status": "affected"
},
{
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"lessThan": "0fab003ef4698e0628060a45a48f14b43ba2a40a",
"versionType": "git",
"status": "affected"
},
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"versionType": "git",
"status": "affected"
},
{
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"status": "affected"
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{
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"versionType": "git",
"status": "affected"
},
{
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"lessThan": "c3e33464746166264334641dc850a36eef7e6326",
"versionType": "git",
"status": "affected"
},
{
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"lessThan": "6785011f8b16abf40b1e9d8b2e332232b3e68822",
"versionType": "git",
"status": "affected"
}
]
},
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "affected",
"programFiles": [
"include/net/ip.h",
"net/bridge/netfilter/nf_conntrack_bridge.c",
"net/ipv4/ip_output.c",
"net/netfilter/nfnetlink_queue.c",
"net/netfilter/xt_CHECKSUM.c",
"net/xfrm/xfrm_output.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "2.6.27",
"status": "affected"
},
{
"version": "0",
"lessThan": "2.6.27",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "5.10.272",
"lessThanOrEqual": "5.10.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "5.15.223",
"lessThanOrEqual": "5.15.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.1.190",
"lessThanOrEqual": "6.1.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.6.159",
"lessThanOrEqual": "6.6.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.12.113",
"lessThanOrEqual": "6.12.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.18.57",
"lessThanOrEqual": "6.18.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "7.2.11",
"lessThanOrEqual": "7.2.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "7.3",
"lessThanOrEqual": "*",
"versionType": "original_commit_for_fix",
"status": "unaffected"
}
]
}
]
}
],
"metrics": {
"cvssMetricV31": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"type": "Secondary",
"cvssData": {
"version": "3.1",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H",
"baseScore": 9.3,
"baseSeverity": "CRITICAL",
"attackVector": "LOCAL",
"attackComplexity": "LOW",
"privilegesRequired": "NONE",
"userInteraction": "NONE",
"scope": "CHANGED",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"availabilityImpact": "HIGH"
},
"exploitabilityScore": 2.5,
"impactScore": 6.0
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"timestamp": "2026-10-16T15:49:03.519458Z",
"id": "CVE-2026-99999",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "total"
}
],
"role": "CISA Coordinator",
"version": "2.0.3"
}
}
]
},
"weaknesses": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"type": "Secondary",
"description": [
{
"lang": "en",
"value": "CWE-20"
}
]
}
],
"references": [
{
"url": "https://git.kernel.org/stable/c/0fab003ef4698e0628060a45a48f14b43ba2a40a",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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{
"url": "https://git.kernel.org/stable/c/32a8b0adaa18e52aaa0b246b5ffe683075354dbb",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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{
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"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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{
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{
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"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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{
"url": "https://pwn.ai/blog/pwnescape",
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{
"url": "https://vercel.com/blog/findings-from-the-1-million-dollar-vercel-sandbox-challenge",
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{
"url": "http://www.openwall.com/lists/oss-security/2026/10/15/5",
"source": "af854a3a-2127-422b-91ae-364da2661108"
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]
}