{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-89549", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-11T19:38:34.723Z", "datePublished": "2026-09-11T19:44:23.928Z", "dateUpdated": "2026-09-11T19:44:23.928Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-09-11T19:44:23.928Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsunrpc: route to a populated pool in svc_pool_for_cpu()\n\nsvc_set_num_threads() spreads the requested threads evenly across the\nservice's pools (base = nrservs / sv_nrpools). When a service runs\nfewer threads than it has pools -- e.g. an nfsd configured with fewer\nthreads than the host has NUMA nodes while running in \"pernode\" or\n\"percpu\" mode -- the trailing pools are left with no threads at all.\n\nsvc_xprt_enqueue() selects a pool from the CPU servicing the transport,\nqueues the transport on that pool's sp_xprts, and only wakes a thread\nfrom the same pool. Each thread services exclusively its own pool, so a\ntransport that lands on a threadless pool is enqueued on sp_xprts and\nnever picked up: the connection hangs indefinitely.\n\nHave svc_pool_for_cpu() skip pools that currently have no threads,\nfalling back to the next populated pool. This trades NUMA locality for\na guarantee that the work is actually serviced. sp_nrthreads is only\nupdated under the service mutex; the lockless read here is a best-effort\nrouting hint, so annotate it with data_race()."}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["net/sunrpc/svc.c"], "versions": [{"version": "bfd241600a3b0db4fe43c859f1460d0a958d924a", "lessThan": "011479cf9a7657d4a3e7cc42a784ac63df594170", "status": "affected", "versionType": "git"}, {"version": "bfd241600a3b0db4fe43c859f1460d0a958d924a", "lessThan": "9d04d64ad192439835ed9884d767353061c3ed6f", "status": "affected", "versionType": "git"}, {"version": "bfd241600a3b0db4fe43c859f1460d0a958d924a", "lessThan": "8f766d2d0b4dabf54f8b35812df2b4f481d13316", "status": "affected", "versionType": "git"}, {"version": "bfd241600a3b0db4fe43c859f1460d0a958d924a", "lessThan": "f6310491c4cdb88af73aa551ec9df1f10a90c709", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["net/sunrpc/svc.c"], "versions": [{"version": "2.6.19", "status": "affected"}, {"version": "0", "lessThan": "2.6.19", "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-rc1", "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": "2.6.19", "versionEndExcluding": "6.12.109"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.19", "versionEndExcluding": "6.18.50"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.19", "versionEndExcluding": "7.2.4"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.19", "versionEndExcluding": "7.3-rc1"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/011479cf9a7657d4a3e7cc42a784ac63df594170"}, {"url": "https://git.kernel.org/stable/c/9d04d64ad192439835ed9884d767353061c3ed6f"}, {"url": "https://git.kernel.org/stable/c/8f766d2d0b4dabf54f8b35812df2b4f481d13316"}, {"url": "https://git.kernel.org/stable/c/f6310491c4cdb88af73aa551ec9df1f10a90c709"}], "title": "sunrpc: route to a populated pool in svc_pool_for_cpu()", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["net/sunrpc/svc.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "011479cf9a7657d4a3e7cc42a784ac63df594170", "status": "affected", "version": "bfd241600a3b0db4fe43c859f1460d0a958d924a", "versionType": "git"}, {"lessThan": "9d04d64ad192439835ed9884d767353061c3ed6f", "status": "affected", "version": "bfd241600a3b0db4fe43c859f1460d0a958d924a", "versionType": "git"}, {"lessThan": "8f766d2d0b4dabf54f8b35812df2b4f481d13316", "status": "affected", "version": "bfd241600a3b0db4fe43c859f1460d0a958d924a", "versionType": "git"}, {"lessThan": "f6310491c4cdb88af73aa551ec9df1f10a90c709", "status": "affected", "version": "bfd241600a3b0db4fe43c859f1460d0a958d924a", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["net/sunrpc/svc.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "2.6.19"}, {"lessThan": "2.6.19", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.109", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.50", "versionType": "semver"}, {"lessThanOrEqual": "7.2.*", "status": "unaffected", "version": "7.2.4", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.3-rc1", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsunrpc: route to a populated pool in svc_pool_for_cpu()\n\nsvc_set_num_threads() spreads the requested threads evenly across the\nservice's pools (base = nrservs / sv_nrpools). When a service runs\nfewer threads than it has pools -- e.g. an nfsd configured with fewer\nthreads than the host has NUMA nodes while running in \"pernode\" or\n\"percpu\" mode -- the trailing pools are left with no threads at all.\n\nsvc_xprt_enqueue() selects a pool from the CPU servicing the transport,\nqueues the transport on that pool's sp_xprts, and only wakes a thread\nfrom the same pool. Each thread services exclusively its own pool, so a\ntransport that lands on a threadless pool is enqueued on sp_xprts and\nnever picked up: the connection hangs indefinitely.\n\nHave svc_pool_for_cpu() skip pools that currently have no threads,\nfalling back to the next populated pool. This trades NUMA locality for\na guarantee that the work is actually serviced. sp_nrthreads is only\nupdated under the service mutex; the lockless read here is a best-effort\nrouting hint, so annotate it with data_race()."}], "id": "CVE-2026-89549", "lastModified": "2026-09-11T20:19:38.373", "metrics": {}, "published": "2026-09-11T20:19:38.373", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/011479cf9a7657d4a3e7cc42a784ac63df594170"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/8f766d2d0b4dabf54f8b35812df2b4f481d13316"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/9d04d64ad192439835ed9884d767353061c3ed6f"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/f6310491c4cdb88af73aa551ec9df1f10a90c709"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{"bugzilla": {"description": "kernel: Linux kernel: sunrpc connection hang due to threadless pool routing", "id": "2532409", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2532409"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.9", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-821", "details": ["A flaw was found in the `sunrpc` component of the Linux kernel. When the `nfsd` service runs with fewer threads than available pools, a transport can be routed to a pool with no active threads. This prevents the connection from being processed, causing it to hang indefinitely. This can lead to a Denial of Service (DoS) condition for affected services."], "name": "CVE-2026-89549", "public_date": "2026-09-11T19:44:23Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-89549\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-89549\nhttps://git.kernel.org/stable/c/011479cf9a7657d4a3e7cc42a784ac63df594170\nhttps://git.kernel.org/stable/c/8f766d2d0b4dabf54f8b35812df2b4f481d13316\nhttps://git.kernel.org/stable/c/9d04d64ad192439835ed9884d767353061c3ed6f\nhttps://git.kernel.org/stable/c/f6310491c4cdb88af73aa551ec9df1f10a90c709"], "threat_severity": "Moderate"}

{"created": "2026-09-12T07:15:10.614603+00:00", "updated": "2026-09-12T07:15:10.614610+00:00", "vendors": [], "weaknesses": ["CWE-362"]}