254 lines
15 KiB
JSON
254 lines
15 KiB
JSON
{
|
|
"dataType": "CVE_RECORD",
|
|
"dataVersion": "5.2",
|
|
"cveMetadata": {
|
|
"cveId": "CVE-2026-89702",
|
|
"assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
|
|
"state": "PUBLISHED",
|
|
"assignerShortName": "Linux",
|
|
"dateReserved": "2026-09-11T19:38:34.750Z",
|
|
"datePublished": "2026-09-11T19:46:19.537Z",
|
|
"dateUpdated": "2026-10-30T12:32:45.423Z"
|
|
},
|
|
"containers": {
|
|
"cna": {
|
|
"providerMetadata": {
|
|
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
|
|
"shortName": "Linux",
|
|
"dateUpdated": "2026-10-30T12:32:45.423Z"
|
|
},
|
|
"descriptions": [
|
|
{
|
|
"lang": "en",
|
|
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnfsd: size fh_verify server sockaddr slot by xpt_locallen\n\nThe nfsd_fh_verify and nfsd_fh_verify_err tracepoints declare the\nserver sockaddr slot sized by xpt_remotelen but fill it from\nxpt_local using xpt_locallen:\n\n TP_STRUCT__entry(\n ...\n __sockaddr(server, rqstp->rq_xprt->xpt_remotelen)\n ...\n )\n TP_fast_assign(\n ...\n __assign_sockaddr(server, &rqstp->rq_xprt->xpt_local,\n rqstp->rq_xprt->xpt_locallen);\n ...\n )\n\nWhen xpt_locallen exceeds xpt_remotelen, __assign_sockaddr's memcpy\nwrites past the reserved ring-buffer slot. In the reverse direction\n(xpt_locallen < xpt_remotelen) the slot is oversized and the\nunwritten tail leaks prior ring-buffer contents to trace consumers.\n\nThe write-past-end case is reachable on NFS/UDP. svc_xprt_set_remote()\nis only called from svc_tcp_accept() (net/sunrpc/svcsock.c) and from\nthe RDMA connect path; svc_create_socket() for UDP calls only\nsvc_xprt_set_local(), so xpt_remotelen stays 0 for the xprt's\nlifetime. Every fh_verify trace for an NFSv2/v3-over-UDP request\nthen copies 16 or 28 bytes from xpt_local into a zero-byte slot.\n\nThe other NFSD tracepoints that record the server address\n(NFSD_TRACE_PROC_CALL_FIELDS, NFSD_TRACE_PROC_RES_FIELDS,\nSVC_RQST_ENDPOINT_FIELDS) already size the server slot by\nxpt_locallen; nfsd_fh_verify and nfsd_fh_verify_err were the only\nexceptions.\n\nFix by sizing the server slot with xpt_locallen so the declared slot\nmatches the copy length. The client slot and its assignment already\nagree on xpt_remotelen and are left untouched."
|
|
}
|
|
],
|
|
"metrics": [
|
|
{
|
|
"cvssV3_1": {
|
|
"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"
|
|
},
|
|
"scenarios": [
|
|
{
|
|
"lang": "en",
|
|
"value": "AV:N - The nfsd_fh_verify and nfsd_fh_verify_err tracepoints run in the in-kernel NFS server while handling NFSv2/v3 RPCs on UDP/2049; a remote packet reaches svc_udp_recvfrom, svc_process, nfsd_proc_getattr/nfsd3_proc_getattr, then fh_verify.\nAC:L - With the nfsd_fh_verify events enabled (a realistic nfsd tracing/perf deployment), every UDP fh_verify deterministically memcpy's 16 or 28 bytes of xpt_local into a 0-byte slot; no race, layout guess, or attacker-uncontrollable condition is required.\nPR:N - AUTH_NULL and AUTH_SYS verify no credentials, and GETATTR uses NFSD_MAY_NOP so a dummy filehandle still hits fh_verify (and nfsd_fh_verify_err on lookup failure); a UDP source-IP spoof or wildcard export satisfies the IP map without an authenticated principal.\nUI:N - The attacker sends crafted NFS/UDP RPCs unilaterally; no administrator or victim-client action is required at exploitation time, and tracing already being enabled is the scored configuration rather than user interaction.\nS:U - The overflow corrupts the host kernel's ftrace/perf ring buffer inside the NFS server's own kernel security authority and does not cross a VM, IOMMU, or sandbox boundary.\nC:H - When the reserved sockaddr slot is larger than xpt_locallen, leftover prior ring-buffer contents including kernel pointers from other events leak to trace consumers; the UDP out-of-bounds write can also corrupt adjacent event headers so later parses treat neighbouring kernel memory as payload.\nI:H - On NFS/UDP, xpt_remotelen stays 0 so __assign_sockaddr copies 16 or 28 bytes of xpt_local past the reserved dynamic array into subsequent ring-buffer bytes and potentially the next sub-buffer page header, which is an out-of-bounds kernel write.\nA:H - Corrupting ring-buffer event headers or the next sub-buffer page metadata can oops or panic the tracer or hang consumers, and a remote peer can repeat the UDP request to force the overflow until the kernel faults."
|
|
}
|
|
]
|
|
}
|
|
],
|
|
"affected": [
|
|
{
|
|
"product": "Linux",
|
|
"vendor": "Linux",
|
|
"defaultStatus": "unaffected",
|
|
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
|
|
"programFiles": [
|
|
"fs/nfsd/trace.h"
|
|
],
|
|
"versions": [
|
|
{
|
|
"version": "dcbebc86850324fbe0a993ce352f0539cd98038a",
|
|
"lessThan": "4c7569ad68fc8b86ca40c7e56ef21460c0344955",
|
|
"status": "affected",
|
|
"versionType": "git"
|
|
},
|
|
{
|
|
"version": "051382885552e12541cc0ebf82092be374a9ed2a",
|
|
"lessThan": "50d9d581d2af80799125ee62617d37e9b6b476a7",
|
|
"status": "affected",
|
|
"versionType": "git"
|
|
},
|
|
{
|
|
"version": "051382885552e12541cc0ebf82092be374a9ed2a",
|
|
"lessThan": "1c6a4d6c20fd42552ffc2c3dfaed2139c9477ee5",
|
|
"status": "affected",
|
|
"versionType": "git"
|
|
},
|
|
{
|
|
"version": "051382885552e12541cc0ebf82092be374a9ed2a",
|
|
"lessThan": "95d064f9828a20ccca5ae90a17be3e2076f25272",
|
|
"status": "affected",
|
|
"versionType": "git"
|
|
},
|
|
{
|
|
"version": "051382885552e12541cc0ebf82092be374a9ed2a",
|
|
"lessThan": "7ff8d6363cffff45654ea85e319f7c0c54226012",
|
|
"status": "affected",
|
|
"versionType": "git"
|
|
},
|
|
{
|
|
"version": "051382885552e12541cc0ebf82092be374a9ed2a",
|
|
"lessThan": "719a10e3f5f868c3c4ac3cf3648c5775d12034bd",
|
|
"status": "affected",
|
|
"versionType": "git"
|
|
},
|
|
{
|
|
"version": "051382885552e12541cc0ebf82092be374a9ed2a",
|
|
"lessThan": "71d068490098b1d23c63b2345e40675d3a1ca763",
|
|
"status": "affected",
|
|
"versionType": "git"
|
|
},
|
|
{
|
|
"version": "62980365d6e894234b29f44fb2bfad4f7f8bb824",
|
|
"status": "affected",
|
|
"versionType": "git"
|
|
},
|
|
{
|
|
"version": "5.15.154",
|
|
"lessThan": "5.15.224",
|
|
"status": "affected",
|
|
"versionType": "semver"
|
|
}
|
|
]
|
|
},
|
|
{
|
|
"product": "Linux",
|
|
"vendor": "Linux",
|
|
"defaultStatus": "affected",
|
|
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
|
|
"programFiles": [
|
|
"fs/nfsd/trace.h"
|
|
],
|
|
"versions": [
|
|
{
|
|
"version": "6.0",
|
|
"status": "affected"
|
|
},
|
|
{
|
|
"version": "0",
|
|
"lessThan": "6.0",
|
|
"status": "unaffected",
|
|
"versionType": "semver"
|
|
},
|
|
{
|
|
"version": "5.15.224",
|
|
"lessThanOrEqual": "5.15.*",
|
|
"status": "unaffected",
|
|
"versionType": "semver"
|
|
},
|
|
{
|
|
"version": "6.1.191",
|
|
"lessThanOrEqual": "6.1.*",
|
|
"status": "unaffected",
|
|
"versionType": "semver"
|
|
},
|
|
{
|
|
"version": "6.6.160",
|
|
"lessThanOrEqual": "6.6.*",
|
|
"status": "unaffected",
|
|
"versionType": "semver"
|
|
},
|
|
{
|
|
"version": "6.12.109",
|
|
"lessThanOrEqual": "6.12.*",
|
|
"status": "unaffected",
|
|
"versionType": "semver"
|
|
},
|
|
{
|
|
"version": "6.18.50",
|
|
"lessThanOrEqual": "6.18.*",
|
|
"status": "unaffected",
|
|
"versionType": "semver"
|
|
},
|
|
{
|
|
"version": "7.2.4",
|
|
"lessThanOrEqual": "7.2.*",
|
|
"status": "unaffected",
|
|
"versionType": "semver"
|
|
},
|
|
{
|
|
"version": "7.3",
|
|
"lessThanOrEqual": "*",
|
|
"status": "unaffected",
|
|
"versionType": "original_commit_for_fix"
|
|
}
|
|
]
|
|
}
|
|
],
|
|
"cpeApplicability": [
|
|
{
|
|
"nodes": [
|
|
{
|
|
"operator": "OR",
|
|
"negate": false,
|
|
"cpeMatch": [
|
|
{
|
|
"vulnerable": true,
|
|
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
|
|
"versionStartIncluding": "5.15.154",
|
|
"versionEndExcluding": "5.15.224"
|
|
},
|
|
{
|
|
"vulnerable": true,
|
|
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
|
|
"versionStartIncluding": "6.0",
|
|
"versionEndExcluding": "6.1.191"
|
|
},
|
|
{
|
|
"vulnerable": true,
|
|
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
|
|
"versionStartIncluding": "6.0",
|
|
"versionEndExcluding": "6.6.160"
|
|
},
|
|
{
|
|
"vulnerable": true,
|
|
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
|
|
"versionStartIncluding": "6.0",
|
|
"versionEndExcluding": "6.12.109"
|
|
},
|
|
{
|
|
"vulnerable": true,
|
|
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
|
|
"versionStartIncluding": "6.0",
|
|
"versionEndExcluding": "6.18.50"
|
|
},
|
|
{
|
|
"vulnerable": true,
|
|
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
|
|
"versionStartIncluding": "6.0",
|
|
"versionEndExcluding": "7.2.4"
|
|
},
|
|
{
|
|
"vulnerable": true,
|
|
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
|
|
"versionStartIncluding": "6.0",
|
|
"versionEndExcluding": "7.3"
|
|
}
|
|
]
|
|
}
|
|
]
|
|
}
|
|
],
|
|
"references": [
|
|
{
|
|
"url": "https://git.kernel.org/stable/c/4c7569ad68fc8b86ca40c7e56ef21460c0344955"
|
|
},
|
|
{
|
|
"url": "https://git.kernel.org/stable/c/50d9d581d2af80799125ee62617d37e9b6b476a7"
|
|
},
|
|
{
|
|
"url": "https://git.kernel.org/stable/c/1c6a4d6c20fd42552ffc2c3dfaed2139c9477ee5"
|
|
},
|
|
{
|
|
"url": "https://git.kernel.org/stable/c/95d064f9828a20ccca5ae90a17be3e2076f25272"
|
|
},
|
|
{
|
|
"url": "https://git.kernel.org/stable/c/7ff8d6363cffff45654ea85e319f7c0c54226012"
|
|
},
|
|
{
|
|
"url": "https://git.kernel.org/stable/c/719a10e3f5f868c3c4ac3cf3648c5775d12034bd"
|
|
},
|
|
{
|
|
"url": "https://git.kernel.org/stable/c/71d068490098b1d23c63b2345e40675d3a1ca763"
|
|
}
|
|
],
|
|
"title": "nfsd: size fh_verify server sockaddr slot by xpt_locallen",
|
|
"x_generator": {
|
|
"engine": "bippy-1.2.0"
|
|
}
|
|
}
|
|
}
|
|
} |