{"api_version":"1","generated_at":"2026-04-23T03:47:14+00:00","cve":"CVE-2026-31486","urls":{"html":"https://cve.report/CVE-2026-31486","api":"https://cve.report/api/cve/CVE-2026-31486.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-31486","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-31486"},"summary":{"title":"hwmon: (pmbus/core) Protect regulator operations with mutex","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nhwmon: (pmbus/core) Protect regulator operations with mutex\n\nThe regulator operations pmbus_regulator_get_voltage(),\npmbus_regulator_set_voltage(), and pmbus_regulator_list_voltage()\naccess PMBus registers and shared data but were not protected by\nthe update_lock mutex. This could lead to race conditions.\n\nHowever, adding mutex protection directly to these functions causes\na deadlock because pmbus_regulator_notify() (which calls\nregulator_notifier_call_chain()) is often called with the mutex\nalready held (e.g., from pmbus_fault_handler()). If a regulator\ncallback then calls one of the now-protected voltage functions,\nit will attempt to acquire the same mutex.\n\nRework pmbus_regulator_notify() to utilize a worker function to\nsend notifications outside of the mutex protection. Events are\nstored as atomics in a per-page bitmask and processed by the worker.\n\nInitialize the worker and its associated data during regulator\nregistration, and ensure it is cancelled on device removal using\ndevm_add_action_or_reset().\n\nWhile at it, remove the unnecessary include of linux/of.h.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-04-22 14:16:46","updated_at":"2026-04-22 14:16:46"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/754bd2b4a084b90b5e7b630e1f423061a9b9b761","name":"https://git.kernel.org/stable/c/754bd2b4a084b90b5e7b630e1f423061a9b9b761","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/2c77ae315f3ce9d2c8e1609be74c9358c1fe4e07","name":"https://git.kernel.org/stable/c/2c77ae315f3ce9d2c8e1609be74c9358c1fe4e07","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/4e9d723d9f198b86f6882a84c501ba1f39e8d055","name":"https://git.kernel.org/stable/c/4e9d723d9f198b86f6882a84c501ba1f39e8d055","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-31486","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-31486","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected ddbb4db4ced1ba784fcd3500179a7291b6c5d7b7 4e9d723d9f198b86f6882a84c501ba1f39e8d055 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected ddbb4db4ced1ba784fcd3500179a7291b6c5d7b7 2c77ae315f3ce9d2c8e1609be74c9358c1fe4e07 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected ddbb4db4ced1ba784fcd3500179a7291b6c5d7b7 754bd2b4a084b90b5e7b630e1f423061a9b9b761 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 3.19","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 3.19 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.21 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.19.11 6.19.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.0 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["drivers/hwmon/pmbus/pmbus_core.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"4e9d723d9f198b86f6882a84c501ba1f39e8d055","status":"affected","version":"ddbb4db4ced1ba784fcd3500179a7291b6c5d7b7","versionType":"git"},{"lessThan":"2c77ae315f3ce9d2c8e1609be74c9358c1fe4e07","status":"affected","version":"ddbb4db4ced1ba784fcd3500179a7291b6c5d7b7","versionType":"git"},{"lessThan":"754bd2b4a084b90b5e7b630e1f423061a9b9b761","status":"affected","version":"ddbb4db4ced1ba784fcd3500179a7291b6c5d7b7","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["drivers/hwmon/pmbus/pmbus_core.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"3.19"},{"lessThan":"3.19","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.21","versionType":"semver"},{"lessThanOrEqual":"6.19.*","status":"unaffected","version":"6.19.11","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.0","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.21","versionStartIncluding":"3.19","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.19.11","versionStartIncluding":"3.19","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.0","versionStartIncluding":"3.19","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nhwmon: (pmbus/core) Protect regulator operations with mutex\n\nThe regulator operations pmbus_regulator_get_voltage(),\npmbus_regulator_set_voltage(), and pmbus_regulator_list_voltage()\naccess PMBus registers and shared data but were not protected by\nthe update_lock mutex. This could lead to race conditions.\n\nHowever, adding mutex protection directly to these functions causes\na deadlock because pmbus_regulator_notify() (which calls\nregulator_notifier_call_chain()) is often called with the mutex\nalready held (e.g., from pmbus_fault_handler()). If a regulator\ncallback then calls one of the now-protected voltage functions,\nit will attempt to acquire the same mutex.\n\nRework pmbus_regulator_notify() to utilize a worker function to\nsend notifications outside of the mutex protection. Events are\nstored as atomics in a per-page bitmask and processed by the worker.\n\nInitialize the worker and its associated data during regulator\nregistration, and ensure it is cancelled on device removal using\ndevm_add_action_or_reset().\n\nWhile at it, remove the unnecessary include of linux/of.h."}],"providerMetadata":{"dateUpdated":"2026-04-22T13:54:11.594Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/4e9d723d9f198b86f6882a84c501ba1f39e8d055"},{"url":"https://git.kernel.org/stable/c/2c77ae315f3ce9d2c8e1609be74c9358c1fe4e07"},{"url":"https://git.kernel.org/stable/c/754bd2b4a084b90b5e7b630e1f423061a9b9b761"}],"title":"hwmon: (pmbus/core) Protect regulator operations with mutex","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-31486","datePublished":"2026-04-22T13:54:11.594Z","dateReserved":"2026-03-09T15:48:24.101Z","dateUpdated":"2026-04-22T13:54:11.594Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-04-22 14:16:46","lastModifiedDate":"2026-04-22 14:16:46","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"31486","Ordinal":"1","Title":"hwmon: (pmbus/core) Protect regulator operations with mutex","CVE":"CVE-2026-31486","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"31486","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nhwmon: (pmbus/core) Protect regulator operations with mutex\n\nThe regulator operations pmbus_regulator_get_voltage(),\npmbus_regulator_set_voltage(), and pmbus_regulator_list_voltage()\naccess PMBus registers and shared data but were not protected by\nthe update_lock mutex. This could lead to race conditions.\n\nHowever, adding mutex protection directly to these functions causes\na deadlock because pmbus_regulator_notify() (which calls\nregulator_notifier_call_chain()) is often called with the mutex\nalready held (e.g., from pmbus_fault_handler()). If a regulator\ncallback then calls one of the now-protected voltage functions,\nit will attempt to acquire the same mutex.\n\nRework pmbus_regulator_notify() to utilize a worker function to\nsend notifications outside of the mutex protection. Events are\nstored as atomics in a per-page bitmask and processed by the worker.\n\nInitialize the worker and its associated data during regulator\nregistration, and ensure it is cancelled on device removal using\ndevm_add_action_or_reset().\n\nWhile at it, remove the unnecessary include of linux/of.h.","Type":"Description","Title":"hwmon: (pmbus/core) Protect regulator operations with mutex"}]}}}