{"id":"CVE-2026-99017","title":"riscv: errata: select RISCV_ALTERNATIVE_EARLY for THEAD GHOSTWRITE","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nriscv: errata: select RISCV_ALTERNATIVE_EARLY for THEAD GHOSTWRITE\n\nerrata_probe_ghostwrite() only marks the CPU as vulnerable when it is\ncalled at the RISCV_ALTERNATIV…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= 4bf97069239bcfca9840936313c7ac35a6e04488 < fa465a7819ecbe5801b78c088d3cadaf2664b8ca","Linux >= 4bf97069239bcfca9840936313c7ac35a6e04488 < 7fee577a2fa78b9a76da015beec1ccf978746ebb","Linux >= 4bf97069239bcfca9840936313c7ac35a6e04488 < 298510bbc7c3017c0faf481c6ea66f1065b657b4","Linux 6.14"],"published":"2026-10-23","updated":"2026-10-23","sourceUpdated":"2026-10-23T12:20:53.518Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-99017","references":[{"url":"https://git.kernel.org/stable/c/fa465a7819ecbe5801b78c088d3cadaf2664b8ca"},{"url":"https://git.kernel.org/stable/c/7fee577a2fa78b9a76da015beec1ccf978746ebb"},{"url":"https://git.kernel.org/stable/c/298510bbc7c3017c0faf481c6ea66f1065b657b4"}],"tags":["cve.org"],"ingestedAt":"2026-10-23T13:24:55.537Z","slug":"CVE-2026-99017","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nriscv: errata: select RISCV_ALTERNATIVE_EARLY for THEAD GHOSTWRITE\n\nerrata_probe_ghostwrite() only marks the CPU as vulnerable when it is\ncalled at the RISCV_ALTERNATIVES_EARLY_BOOT stage, and the mitigation\nin ghostwrite_enable_mitigation() only takes effect if the vulnerable\nstate was recorded before the boot alternatives are patched.\n\nThe early boot stage is only executed when CONFIG_RISCV_ALTERNATIVE_EARLY\nis enabled, which currently is only selected by ERRATA_THEAD_MAE. In a\nkernel built with ERRATA_THEAD_GHOSTWRITE=y but ERRATA_THEAD_MAE=n, the\nearly alternatives never run, so ghostwrite_state is never set to\nVULNERABLE: ghostwrite_enable_mitigation() returns false, xtheadvector\nremains enabled, and sysfs reports \"Not affected\" on a vulnerable\nT-Head C9xx CPU.\n\nSelect RISCV_ALTERNATIVE_EARLY from ERRATA_THEAD_GHOSTWRITE so that the\nvulnerability is detected in the early boot stage and the default\nmitigation is applied.\n\n## Affected\n\n- `Linux >= 4bf97069239bcfca9840936313c7ac35a6e04488 < fa465a7819ecbe5801b78c088d3cadaf2664b8ca`\n- `Linux >= 4bf97069239bcfca9840936313c7ac35a6e04488 < 7fee577a2fa78b9a76da015beec1ccf978746ebb`\n- `Linux >= 4bf97069239bcfca9840936313c7ac35a6e04488 < 298510bbc7c3017c0faf481c6ea66f1065b657b4`\n- `Linux 6.14`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}