CVE-2026-93229
📛 CVE Title
nfsd: add missing read barrier to rpc_status_get dumpit seqcount retry
Description
In the Linux kernel, the following vulnerability has been resolved: nfsd: add missing read barrier to rpc_status_get dumpit seqcount retry The hand-rolled seqcount-like protocol in nfsd_nl_rpc_status_get_dumpit() is missing a read memory barrier (smp_rmb) before its second counter check. The standard kernel read_seqcount_retry() includes smp_rmb() to ensure that all data reads complete before the counter is re-checked. Without this barrier, on weakly-ordered architectures (ARM, POWER), the CPU may reorder field reads past the second counter check, making the retry logic ineffective: it could observe a consistent counter pair while reading fields that have been concurrently modified by the writer. Add smp_rmb() before the second counter check to order the field reads ahead of it, matching the barrier semantics of the standard seqcount read-side. The begin-side smp_load_acquire() already pairs with the smp_store_release() in nfsd_dispatch(); with the smp_rmb() now ordering the field reads, the retry check no longer needs acquire semantics and reads the counter with a plain READ_ONCE(), as read_seqcount_retry() does. [ cel: Use READ_ONCE instead of smp_load_acquire() ]
Overview
- State
- PUBLISHED
- Assigner (CNA)
- Linux
- CVSS severity
- HIGH
- CVSS score
- 7.1 / 10
- CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H- Effective score
- 7.1 / 10 HIGH source: CNA overview
- CWE(s)
- —
- Reserved
- 2026-09-17
- Published
- 2026-09-24 15:29 UTC
- Last updated
- 2026-09-25 05:09 UTC
- Source
- https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/93xxx/CVE-2026-93229.json
- Linked Threat
- CVE-2026-93229 — nfsd: add missing read barrier to rpc_status_get dumpit seqcount retry
NVD triage scoring NVD CVE 2.0
Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.
- NVD published
- 2026-09-24 16:17:18 UTC
- NVD last modified
- 2026-09-24 16:17:18 UTC
NVD / KEV / EPSS data refreshed 2026-09-25 04:31 UTC. Re-run the 🛰 Backfill from NVD button above to refresh.
European Union Vulnerability Database ENISA EUVD
ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.
- EUVD ID
-
EUVD-2026-86234 - Assigner
- Linux
- Published
- Sep 24, 2026, 3:29:14 PM
- Updated
- Sep 25, 2026, 5:09:49 AM
- EUVD base score (CVSS 3.1)
-
7.1 / 10
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H - EUVD-reported EPSS
- 0.0000
- Vendors
- Linux
- Products
-
Linux (bd9d6a3efa9709e653aafbeb859289feccb8e70c <9b5f6475006cd8e3b5b99b8eb3cd74dbb1ce9df8)Linux (patch: 6.18.50)Linux (patch: 6.12.109)Linux (patch: 7.2.4)Linux (patch: 0)Linux (patch: 7.3-rc1)Linux (6.7)Linux (bd9d6a3efa9709e653aafbeb859289feccb8e70c <f501f2f4ec1d2dfe39e21c98630314074a9b30b0)Linux (bd9d6a3efa9709e653aafbeb859289feccb8e70c <a71f161a857117e8e0264deb7d14fff5c98adcf5)Linux (bd9d6a3efa9709e653aafbeb859289feccb8e70c <1aea0482b98ecd7d0249204665f2ad4ad517f66b)
- Aliases
-
GHSA-fg62-2q3c-3w5h
ENISA description: In the Linux kernel, the following vulnerability has been resolved: nfsd: add missing read barrier to rpc_status_get dumpit seqcount retry The hand-rolled seqcount-like protocol in nfsd_nl_rpc_status_get_dumpit() is missing a read memory barrier (smp_rmb) before its second counter check. The standard kernel read_seqcount_retry() includes smp_rmb() to ensure that all data reads complete before the counter is re-checked. Without this barrier, on weakly-ordered architectures (ARM, POWER), the CPU may reorder field reads past the second counter check, making the retry logic ineffective: it could observe a consistent counter pair while reading fields that have been concurrently modified by the writer. Add smp_rmb() before the second counter check to order the field reads ahead of it, matching the barrier semantics of the standard seqcount read-side. The begin-side smp_load_acquire() already pairs with the smp_store_release() in nfsd_dispatch(); with the smp_rmb() now ordering the field reads, the retry check no longer needs acquire semantics and reads the counter with a plain READ_ONCE(), as read_seqcount_retry() does. [ cel: Use READ_ONCE instead of smp_load_acquire() ]
EUVD references (4)
Affected products (2)
| Vendor | Product | Versions | Platforms |
|---|---|---|---|
| Linux | Linux |
bd9d6a3efa9709e653aafbeb859289feccb8e70c (affected),
bd9d6a3efa9709e653aafbeb859289feccb8e70c (affected),
bd9d6a3efa9709e653aafbeb859289feccb8e70c (affected),
bd9d6a3efa9709e653aafbeb859289feccb8e70c (affected)
|
— |
| Linux | Linux |
6.7 (affected),
0 (unaffected),
6.12.109 (unaffected),
6.18.50 (unaffected),
7.2.4 (unaffected),
7.3-rc1 (unaffected)
|
— |
Vendor references (4)
References embedded in the original CVE record by the assigning CNA.
Web references (0)
DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.
No web references attached yet.
NVD-tagged references (4)
Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.
- https://git.kernel.org/stable/c/1aea0482b98ecd7d0249204665f2ad4ad517f66b 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- https://git.kernel.org/stable/c/9b5f6475006cd8e3b5b99b8eb3cd74dbb1ce9df8 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- https://git.kernel.org/stable/c/a71f161a857117e8e0264deb7d14fff5c98adcf5 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- https://git.kernel.org/stable/c/f501f2f4ec1d2dfe39e21c98630314074a9b30b0 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Remediations (15)
Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.
-
web:blogs.oracle.com
This Critical Patch Update contains 481 new security patches across the product families listed below. Please note that an MOS note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at April 2026 Critical Patch Update: Executive Summary and Analysis.
2026-09-25 10:45 UTC -
web:msrc.microsoft.com
The Microsoft Security Response Center (MSRC) investigates all reports of security vulnerabilities affecting Microsoft products and services, and provides the information here as part of the ongoing effort to help you manage security risks and help keep your systems protected.
2026-09-25 10:45 UTC -
web:patchmypc.com
You can find the production release history below for 2026 .
2026-09-25 10:45 UTC -
web:sec.cloudapps.cisco.com
On September 16, 2026 , the Cisco Product Security Incident Response Team (PSIRT) published the advisories that are listed in the following tables. To remediate these vulnerabilities, Cisco strongly recommends that customers upgrade to the fixed software that is indicated in the advisories. For more information about changes in Cisco PSIRT vulnerability disclosure, see Strengthening the ...
2026-09-25 10:45 UTC -
web:www.action1.com
This CISO-focused summary highlights the vulnerabilities and critical infrastructure risks that should take priority for remediation following Microsoft's September 2026 Patch Tuesday release.
2026-09-25 10:45 UTC -
web:www.aikido.dev
CVE remediation is fixing known flaws in the software you run. Why upgrading often fails, what remediation actually involves, and how backporting fixes it.
2026-09-25 10:45 UTC -
web:www.fastly.com
To help mitigate exploitation attempts, Fastly Next-Gen WAF has shipped a virtual patch for CVE - 2026 -82329 allowing customers to protect their instances immediately. For remediation steps and vendor patching details, see the Actionable Recommendations section at the end of this post.
2026-09-25 10:45 UTC -
web:www.oracle.com
This Critical Patch Update contains 481 new security patches across the product families listed below. Please note that an MOS note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at April 2026 Critical Patch Update: Executive Summary and Analysis.
2026-09-25 10:45 UTC -
web:www.oracle.com
This Critical Patch Update contains 1448 new security patches across the product families listed below. Please note that a My Oracle Support (MOS) note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at July 2026 Critical Patch Update: Executive Summary and Analysis.
2026-09-25 10:45 UTC -
web:www.secpod.com
Patch Timeline & Exploitation Gap Analysis The September 16, 2026 dataset contains three CISA KEV vulnerabilities. Each record was added to the catalog on September 16, 2026 and assigned a remediation deadline of September 19, 2026 . Consequently, all three vulnerabilities have an identical three-calendar-day KEV inclusion-to- remediation window.
2026-09-25 10:45 UTC -
web:blog.qualys.com
Microsoft kicks off September with its monthly Patch Tuesday release, delivering fixes for security vulnerabilities affecting its products. The security updates are packed with security fixes…
2026-09-25 21:26 UTC -
web:helpx.adobe.com
This page contains important information regarding security vulnerabilities that could affect specific versions of Adobe products. Use this information to take the prescribed corrective actions.
2026-09-25 21:26 UTC -
web:support.sap.com
On 14 th of July 2026 , SAP security patch day saw the release of 16 new security notes and 1 Github security advisory. There are 3 updates to previously released security notes.
2026-09-25 21:26 UTC -
web:support.servicenow.com
What you need to know: On September 24, 2026 , ServiceNow issued CVE - 2026 -86857, CVE - 2026 -86858, CVE - 2026 -13016, CVE - 2026 -86859, and CVE - 2026 -86860. Each of these security issues was identified through internal security testing, customer security assessments, or reports submitted through ServiceNow's responsible disclosure and bug bounty programs and was remediated independently. For security ...
2026-09-25 21:26 UTC -
web:www.crowdstrike.com
Microsoft has released security updates for 972 vulnerabilities, including two exploited zero-days and 113 critical, in its September 2026 Patch Tuesday rollout.
2026-09-25 21:26 UTC
AI Forensic Analysis
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Raw JSON
The full cvelistV5 record. Download as CVE-2026-93229.json.
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{
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"version": "6.12.109",
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{
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{
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"status": "unaffected",
"version": "7.3-rc1",
"versionType": "original_commit_for_fix"
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{
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},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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"vulnerable": true
},
{
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"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnfsd: add missing read barrier to rpc_status_get dumpit seqcount retry\n\nThe hand-rolled seqcount-like protocol in nfsd_nl_rpc_status_get_dumpit()\nis missing a read memory barrier (smp_rmb) before its second counter\ncheck. The standard kernel read_seqcount_retry() includes smp_rmb()\nto ensure that all data reads complete before the counter is re-checked.\n\nWithout this barrier, on weakly-ordered architectures (ARM, POWER),\nthe CPU may reorder field reads past the second counter check, making\nthe retry logic ineffective: it could observe a consistent counter pair\nwhile reading fields that have been concurrently modified by the writer.\n\nAdd smp_rmb() before the second counter check to order the field reads\nahead of it, matching the barrier semantics of the standard seqcount\nread-side. The begin-side smp_load_acquire() already pairs with the\nsmp_store_release() in nfsd_dispatch(); with the smp_rmb() now ordering\nthe field reads, the retry check no longer needs acquire semantics and\nreads the counter with a plain READ_ONCE(), as read_seqcount_retry()\ndoes.\n\n[ cel: Use READ_ONCE instead of smp_load_acquire() ]"
}
],
"metrics": [
{
"cvssV3_1": {
"baseScore": 7.1,
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H",
"version": "3.1"
},
"scenarios": [
{
"lang": "en",
"value": "AV:L - The missing smp_rmb is in nfsd_nl_rpc_status_get_dumpit(), reached only via NFSD_CMD_RPC_STATUS_GET over AF_NETLINK (nfsd_nl_ops dumpit). Remote NFS RPCs in nfsd_dispatch() only write rq_status_counter and never enter dumpit, so exploitation requires local netlink.\nAC:L - The attacker loops NFSD_CMD_RPC_STATUS_GET while sending NFSv4 COMPOUNDs with more than eight ops so nfsd_dispatch() smp_store_release()s rq_status_counter and nfsd4_release_compoundargs() mutates args->ops/opcnt. Both sides of the seqcount race are attacker-driven; weakly-ordered ARM/POWER where the missing smp_rmb matters is mainstream.\nPR:L - NFSD_CMD_RPC_STATUS_GET is registered in nfsd_nl_ops with GENL_CMD_CAP_DUMP and no GENL_ADMIN_PERM, so genl_family_rcv_msg() skips the CAP_NET_ADMIN check. Any unprivileged process in the nfsd network namespace can invoke the dump.\nUI:N - The attacker issues the NFSD_CMD_RPC_STATUS_GET dump and the concurrent NFSv4 COMPOUNDs themselves. No separate victim action such as mounting a filesystem or opening a device is required.\nS:U - The torn and out-of-bounds reads occur in host-kernel nfsd_nl_rpc_status_get_dumpit() on the local machine. Impact stays inside one security authority and is not a VM escape, IOMMU bypass, or other cross-boundary breakout.\nC:H - Without smp_rmb(), dumpit can pass the rq_status_counter retry and still load args->opcnt before nfsd4_release_compoundargs() zeros it and args->ops after it is switched to iops[8]. Indices 8-15 then read adjacent slab at nfsd4_op stride and return those u32s via NFSD_A_RPC_STATUS_COMPOUND_OPS.\nI:N - nfsd_nl_rpc_status_get_dumpit() only copies opnum, xid, addresses and related fields into a stack nfsd_genl_rqstp for netlink. The missing retry barrier yields an out-of-bounds or torn read, not an out-of-bounds write, use-after-free write, or control-flow hijack.\nA:H - Slots 8-15 are sampled at sizeof(struct nfsd4_op) stride past the trailing iops[8] array in kmalloc'd nfsd4_compoundargs into adjacent or unmapped slab pages, which can oops nfsd_nl_rpc_status_get_dumpit() even if the leak is not turned into a stable read."
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-09-25T05:09:49.321Z",
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"shortName": "Linux"
},
"references": [
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"url": "https://git.kernel.org/stable/c/f501f2f4ec1d2dfe39e21c98630314074a9b30b0"
},
{
"url": "https://git.kernel.org/stable/c/1aea0482b98ecd7d0249204665f2ad4ad517f66b"
},
{
"url": "https://git.kernel.org/stable/c/9b5f6475006cd8e3b5b99b8eb3cd74dbb1ce9df8"
},
{
"url": "https://git.kernel.org/stable/c/a71f161a857117e8e0264deb7d14fff5c98adcf5"
}
],
"title": "nfsd: add missing read barrier to rpc_status_get dumpit seqcount retry",
"x_generator": {
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"cveMetadata": {
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"cveId": "CVE-2026-93229",
"datePublished": "2026-09-24T15:29:14.322Z",
"dateReserved": "2026-09-17T16:02:15.094Z",
"dateUpdated": "2026-09-25T05:09:49.321Z",
"state": "PUBLISHED"
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