linux — security advisory
In the Linux kernel, the following vulnerability has been resolved: arm64/fpsimd: Avoid clobbering kernel FPSIMD state with SMSTOP On system with SME, a thread's kernel FPSIMD state may be erroneously clobbered during a context switch immediately after that state is restored. Systems without SME are unaffected. If the CPU happens to be in streaming SVE mode before a context switch to a thread with kernel FPSIMD state, fpsimd_thread_switch() will restore the kernel FPSIMD state using fpsimd_load_kernel_state() while the CPU is still in streaming SVE mode. When fpsimd_thread_switch() subsequently calls fpsimd_flush_cpu_state(), this will execute an SMSTOP, causing an exit from streaming SVE mode. The exit from streaming SVE mode will cause the hardware to reset a number of FPSIMD/SVE/SME registers, clobbering the FPSIMD state. Fix this by calling fpsimd_flush_cpu_state() before restoring the kernel FPSIMD state.
- Products
- linux
- Affected versions
- Not specified
- Fixed versions
- 6.12.35-1
- CVEs
- CVE-2025-38169
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 30 Oct 2026, 19:58 UTC · Revision 1
Source evidence
In the Linux kernel, the following vulnerability has been resolved: arm64/fpsimd: Avoid clobbering kernel FPSIMD state with SMSTOP On system with SME, a thread's kernel FPSIMD state may be erroneously clobbered during a context switch immediately after that state is restored. Systems without SME are unaffected. If the CPU happens to be in streaming SVE mode before a context switch to a thread with kernel FPSIMD state, fpsimd_thread_switch() will restore the kernel FPSIMD state using fpsimd_load_kernel_state() while the CPU is still in streaming SVE mode. When fpsimd_thread_switch() subsequently calls fpsimd_flush_cpu_state(), this will execute an SMSTOP, causing an exit from streaming SVE mode. The exit from streaming SVE mode will cause the hardware to reset a number of FPSIMD/SVE/SME registers, clobbering the FPSIMD state. Fix this by calling fpsimd_flush_cpu_state() before restoring the kernel FPSIMD state.
osv:DEBIAN-CVE-2025-38169
linux
Fixed versions: 6.12.35-1
linux
Fixed versions: 6.12.35-1
Complete source record
{
"id": "f2765c3a223b70b0e78fc5e026c2a5a86efa54a2d74996341e42e057473e4de7",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2025-38169",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2025-38169",
"summary": "In the Linux kernel, the following vulnerability has been resolved: arm64/fpsimd: Avoid clobbering kernel FPSIMD state with SMSTOP On system with SME, a thread's kernel FPSIMD state may be erroneously clobbered during a context switch immediately after that state is restored. Systems without SME are unaffected. If the CPU happens to be in streaming SVE mode before a context switch to a thread with kernel FPSIMD state, fpsimd_thread_switch() will restore the kernel FPSIMD state using fpsimd_load_kernel_state() while the CPU is still in streaming SVE mode. When fpsimd_thread_switch() subsequently calls fpsimd_flush_cpu_state(), this will execute an SMSTOP, causing an exit from streaming SVE mode. The exit from streaming SVE mode will cause the hardware to reset a number of FPSIMD/SVE/SME registers, clobbering the FPSIMD state. Fix this by calling fpsimd_flush_cpu_state() before restoring the kernel FPSIMD state.",
"evidence": "osv:DEBIAN-CVE-2025-38169",
"products": [
{
"name": {
"value": "linux",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
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{
"name": {
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"severity": "medium",
"structured": {
"id": "DEBIAN-CVE-2025-38169",
"aliases": [
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"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"
}
],
"affected": [
{
"ranges": [
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"type": "ECOSYSTEM",
"events": [
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{
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"package": {
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"purl": "pkg:deb/debian/linux?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2025-38169.json"
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"ecosystem_specific": {
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}
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{
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"package": {
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"ecosystem": "Debian:14"
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"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2025-38169.json"
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"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-16T09:47:31.247998776Z",
"provider": "osv",
"upstream": [
"CVE-2025-38169"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2025-38169"
]
},
"related_cves": [
{
"value": "CVE-2025-38169",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 338620,
"published_at": "2025-07-03T09:15:32.517+00:00"
}