{"id":"CVE-2025-71111","url":"https://www.cyber-defence.io/tools/cve/CVE-2025-71111","generatedAt":"2026-10-28T09:26:15.401Z","title":"In the Linux kernel, the following vulnerability has been resolved: hwmon: (w83791d) Convert macros to functions to avoid TOCTOU The macro FAN_FROM_REG evaluates its arguments multiple times.","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nhwmon: (w83791d) Convert macros to functions to avoid TOCTOU\n\nThe macro FAN_FROM_REG evaluates its arguments multiple times. When used\nin lockless contexts involving shared driver data, this leads to\nTime-of-Check to Time-of-Use (TOCTOU) race conditions, potentially\ncausing divide-by-zero errors.\n\nConvert the macro to a static function. This guarantees that arguments\nare evaluated only once (pass-by-value), preventing the race\nconditions.\n\nAdditionally, in store_fan_div, move the calculation of the minimum\nlimit inside the update lock. This ensures that the read-modify-write\nsequence operates on consistent data.\n\nAdhere to the principle of minimal changes by only converting macros\nthat evaluate arguments multiple times and are used in lockless\ncontexts.","published":"2026-01-14T15:16:00.000Z","lastModified":"2026-10-19T19:17:13.000Z","status":"Modified","sourceIdentifier":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","cvss":{"version":"3.1","score":4.7,"severity":"MEDIUM","vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H"},"cwe":["CWE-367","CWE-362"],"affected":["linux/linux kernel"],"epss":{"score":0.00105,"percentile":0.01072,"date":"2026-10-27","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (0.10%). Track it; it rarely justifies an emergency change on its own."},"changes":[],"references":[{"url":"https://git.kernel.org/stable/c/3dceb68f6ad33156032ef4da21a93d84059cca6d","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/670d7ef945d3a84683594429aea6ab2cdfa5ceb4","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/a9fb6e8835a22f5796c1182ed612daed3fd273af","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/bf5b03227f2e6d4360004886d268f9df8993ef8f","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/c8cf0c2bdcccc6634b6915ff793b844e12436680","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/f2b579a0c37c0df19603d719894a942a295f634a","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/f94800fbc26ccf7c81eb791707b038a57aa39a18","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2025-71111","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}