CVE-2026-63912
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: xfrm: esp: restore combined single-frag length gate The ESP out-of-place fast path appends the trailer in esp_output_head() before esp_output_tail() allocates the destination page frag. The head-side gate currently checks skb->data_len and tailen separately, but the tail code allocates a single destination frag from the combined post-trailer skb->data_len. Reject the page-frag fast path when the combined aligned length exceeds a page. Otherwise skb_page_frag_refill() may fall back to a single page while the destination sg still spans the combined skb->data_len. Restore this combined-length page gate for both IPv4 and IPv6.
Severity
CRITICAL
CVSS score
9.8
(v3.1)
Vulnerability status
Undergoing Analysis
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-07-19 16:17:09.097000
Last modified
2026-10-19 21:17:10.230000
View original CVE JSON
{
"id": "CVE-2026-63912",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2026-07-19T16:17:09.097",
"lastModified": "2026-10-19T21:17:10.230",
"vulnStatus": "Undergoing Analysis",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nxfrm: esp: restore combined single-frag length gate\n\nThe ESP out-of-place fast path appends the trailer in esp_output_head()\nbefore esp_output_tail() allocates the destination page frag. The\nhead-side gate currently checks skb->data_len and tailen separately, but\nthe tail code allocates a single destination frag from the combined\npost-trailer skb->data_len.\n\nReject the page-frag fast path when the combined aligned length exceeds a\npage. Otherwise skb_page_frag_refill() may fall back to a single page while\nthe destination sg still spans the combined skb->data_len.\n\nRestore this combined-length page gate for both IPv4 and IPv6."
}
],
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "unaffected",
"programFiles": [
"net/ipv4/esp4.c",
"net/ipv6/esp6.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
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{
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{
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{
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},
{
"version": "5.15.36",
"lessThan": "5.15.210",
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"status": "affected"
},
{
"version": "4.14.288",
"lessThan": "4.15",
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"status": "affected"
},
{
"version": "4.19.252",
"lessThan": "4.20",
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},
{
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},
{
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}
]
},
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "affected",
"programFiles": [
"net/ipv4/esp4.c",
"net/ipv6/esp6.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
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"status": "affected"
},
{
"version": "0",
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"status": "unaffected"
},
{
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},
{
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},
{
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},
{
"version": "6.6.143",
"lessThanOrEqual": "6.6.*",
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"status": "unaffected"
},
{
"version": "6.12.93",
"lessThanOrEqual": "6.12.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.18.35",
"lessThanOrEqual": "6.18.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "7.0.12",
"lessThanOrEqual": "7.0.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "7.1",
"lessThanOrEqual": "*",
"versionType": "original_commit_for_fix",
"status": "unaffected"
}
]
}
]
}
],
"metrics": {
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{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"type": "Secondary",
"cvssData": {
"version": "3.1",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"baseScore": 9.8,
"baseSeverity": "CRITICAL",
"attackVector": "NETWORK",
"attackComplexity": "LOW",
"privilegesRequired": "NONE",
"userInteraction": "NONE",
"scope": "UNCHANGED",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"availabilityImpact": "HIGH"
},
"exploitabilityScore": 3.9,
"impactScore": 5.9
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"timestamp": "2026-10-16T15:33:08.898705Z",
"id": "CVE-2026-63912",
"options": [
{
"exploitation": "none"
},
{
"automatable": "yes"
},
{
"technicalImpact": "total"
}
],
"role": "CISA Coordinator",
"version": "2.0.3"
}
}
]
},
"weaknesses": [
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"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"type": "Secondary",
"description": [
{
"lang": "en",
"value": "CWE-125"
}
]
}
],
"references": [
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"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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}