{"id":"CVE-2025-38169","title":"In the Linux kernel, the following vulnerability has been resolved:\n\narm64/fpsimd: Avoid clobbering kernel FPSIMD state with SMSTOP\n\nOn system with SME, a thread's kernel FPSIMD state may be erroneously\nclobbered during a context switch …","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\narm64/fpsimd: Avoid clobbering kernel FPSIMD state with SMSTOP\n\nOn system with SME, a thread's kernel FPSIMD state may be erroneously\nclobbered during a context switch …","severity":"high","cvss":7.8,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","cwe":["CWE-368"],"vendor":"linux","product":"linux_kernel","affected":["linux_kernel >= 6.8.12, < 6.9","linux_kernel >= 6.9.3, < 6.12.34","linux_kernel >= 6.13, < 6.15.3"],"patched":["linux_kernel 6.15.3"],"published":"2025-07-03","updated":"2026-10-15","sourceUpdated":"2026-10-15T22:18:32.380","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2025-38169","references":[{"url":"https://git.kernel.org/stable/c/01098d893fa8a6edb2b56e178b798e3e6b674f02","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/55d52af498daea75aa03ba9b7e444c8ae495ac20","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/a305821f597ec943849d3e53924adb88c61ed682","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2025/cve-2025-38169.json"},{"url":"https://access.redhat.com/security/cve/CVE-2025-38169"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2376067"},{"url":"https://www.cve.org/CVERecord?id=CVE-2025-38169"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2025-38169"},{"url":"https://lore.kernel.org/linux-cve-announce/2025070342-CVE-2025-38169-11b6@gregkh/T"}],"tags":["nvd","csaf","vex","red-hat","cve.org","score-dispute"],"epss":0.00173,"epssPercentile":0.06654,"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-10-15T21:48:10.598358Z"},"scores":{"nvd":7.8,"vendor":5.5,"cna":7.8},"ingestedAt":"2026-10-15T22:48:25.496Z","slug":"CVE-2025-38169","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\narm64/fpsimd: Avoid clobbering kernel FPSIMD state with SMSTOP\n\nOn system with SME, a thread's kernel FPSIMD state may be erroneously\nclobbered during a context switch immediately after that state is\nrestored. Systems without SME are unaffected.\n\nIf the CPU happens to be in streaming SVE mode before a context switch\nto a thread with kernel FPSIMD state, fpsimd_thread_switch() will\nrestore the kernel FPSIMD state using fpsimd_load_kernel_state() while\nthe CPU is still in streaming SVE mode. When fpsimd_thread_switch()\nsubsequently calls fpsimd_flush_cpu_state(), this will execute an\nSMSTOP, causing an exit from streaming SVE mode. The exit from\nstreaming SVE mode will cause the hardware to reset a number of\nFPSIMD/SVE/SME registers, clobbering the FPSIMD state.\n\nFix this by calling fpsimd_flush_cpu_state() before restoring the kernel\nFPSIMD state.\n\n## Affected\n\n- `linux_kernel >= 6.8.12, < 6.9`\n- `linux_kernel >= 6.9.3, < 6.12.34`\n- `linux_kernel >= 6.13, < 6.15.3`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `linux_kernel 6.15.3`\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9 · no fix planned: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9 · updated 2026-10-16 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2025/cve-2025-38169.json)","depth":"twilight","depthScore":43,"depthScoreParts":{"impact":42.9,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":230045,"id":"CVE-2025-38169","ts":1793124775116,"field":"cvss","old":"5.5","new":"7.8"},{"seq":230044,"id":"CVE-2025-38169","ts":1793124775116,"field":"severity","old":"medium","new":"high"},{"seq":223727,"id":"CVE-2025-38169","ts":1792238377954,"field":"cvss","old":"7.8","new":"5.5"},{"seq":223726,"id":"CVE-2025-38169","ts":1792238377954,"field":"severity","old":"high","new":"medium"}]}