{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-72395","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-08-09T03:40:39.924Z","datePublished":"2026-08-15T05:56:22.400Z","dateUpdated":"2026-08-17T05:43:38.599Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-08-17T05:43:38.599Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nhwmon: (pmbus) Fix passing events to regulator core\n\nSashiko reports:\n\nCommit 754bd2b4a084 (\"hwmon: (pmbus/core) Protect regulator operations with\nmutex\") introduced a worker to batch regulator events over time using\natomic_or(). The delayed worker then passes the combined bitmask unmodified\nto regulator_notifier_call_chain().\n\nThe core regulator subsystem's regulator_handle_critical() function\nevaluates the event parameter using a strict switch statement. If\nmultiple distinct faults occur before the worker runs (e.g.,\nREGULATOR_EVENT_UNDER_VOLTAGE | REGULATOR_EVENT_OVER_CURRENT), the combined\nbitmask fails to match any case. This leaves the reason as NULL and\ncompletely bypasses the critical hw_protection_trigger().\n\nFix the problem by passing events bit by bit to the regulator event\nhandler."}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H","baseScore":7.1,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - The flaw is only reachable through the PMBus SMBALERT threaded IRQ handler (pmbus_fault_handler) that reads hardware fault status over I2C; there is no network, adjacent-radio, or direct physical-device API path, but local actors on PMBus-equipped servers, routers, and embedded boards can induce multi-fault conditions.\nAC:L - _pmbus_get_flags() ORs multiple REGULATOR_EVENT_* bits from a single STATUS read, and pmbus_regulator_notify() further batches concurrent IRQs via atomic_or() before the worker runs, so combined masks like UNDER_VOLTAGE|OVER_CURRENT are produced deterministically without races or layout dependencies the attacker cannot influence.\nPR:L - Triggering the IRQ requires causing real PMBus regulator fault bits (e.g., over-current plus under-voltage during supply stress), which an unprivileged local user can induce through heavy workload and power instability on affected platforms; CAP_NET_ADMIN/user-namespace tricks are not needed and no init-namespace root capability is required.\nUI:N - Once fault conditions are present the SMBALERT IRQ and workqueue fire automatically through pmbus_fault_handler and pmbus_regulator_notify_worker; no separate victim action such as mounting media, plugging hardware, or approving a prompt is required.\nS:U - The impact is bypassing kernel hw_protection_trigger() orderly shutdown/reboot for system-critical PMBus regulators on the same host; it does not cross VM, IOMMU, or sandbox security boundaries and is not a guest-to-host escape.\nC:N - This is a notifier bit-mask logic error that leaves regulator_handle_critical() with a NULL reason; there is no kernel memory corruption, use-after-free, or out-of-bounds access that could disclose pointers or arbitrary memory.\nI:H - When multiple distinct fault events are combined, hw_protection_trigger() is completely skipped for system-critical regulators, defeating the kernel's mandatory emergency shutdown policy and allowing continued operation under simultaneous critical under-voltage/over-current/fail conditions that can corrupt power hardware.\nA:H - Bypassing hw_protection_trigger() during simultaneous critical PMBus regulator faults prevents the intended emergency orderly_poweroff/reboot, leaving telecom, data-center, and embedded systems running under dangerous rail conditions that can cause hardware failure, forced resets, and sustained denial of service."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/hwmon/pmbus/pmbus_core.c"],"versions":[{"version":"b26849cffaa7c43355b82e9bef3725e786973a1a","lessThan":"2106bf4056858fcce3624e0c51f6fee4d41d3f2f","status":"affected","versionType":"git"},{"version":"acf04e2863132f6d9222f71f3a76fb9782cbe061","lessThan":"48fe43666950efefb7ac5fbdc012c1b3604096bf","status":"affected","versionType":"git"},{"version":"4e9d723d9f198b86f6882a84c501ba1f39e8d055","lessThan":"489291b6b56978cc50d34e8e13f9636ea296ba8a","status":"affected","versionType":"git"},{"version":"754bd2b4a084b90b5e7b630e1f423061a9b9b761","lessThan":"b0ff6b6ae9c5183ef701ece7016698bde5a5bfba","status":"affected","versionType":"git"},{"version":"754bd2b4a084b90b5e7b630e1f423061a9b9b761","lessThan":"9ef7dacd44216bf5ea05c8aef49eba4d145f4047","status":"affected","versionType":"git"},{"version":"2c77ae315f3ce9d2c8e1609be74c9358c1fe4e07","status":"affected","versionType":"git"},{"version":"6.6.143","lessThan":"6.6.145","status":"affected","versionType":"semver"},{"version":"6.12.92","lessThan":"6.12.97","status":"affected","versionType":"semver"},{"version":"6.18.21","lessThan":"6.18.40","status":"affected","versionType":"semver"},{"version":"6.19.11","lessThan":"6.20","status":"affected","versionType":"semver"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/hwmon/pmbus/pmbus_core.c"],"versions":[{"version":"7.0","status":"affected"},{"version":"0","lessThan":"7.0","status":"unaffected","versionType":"semver"},{"version":"6.6.145","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.97","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.40","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.1.5","lessThanOrEqual":"7.1.*","status":"unaffected","versionType":"semver"},{"version":"7.2","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.6.143","versionEndExcluding":"6.6.145"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.12.92","versionEndExcluding":"6.12.97"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.18.21","versionEndExcluding":"6.18.40"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"7.0","versionEndExcluding":"7.1.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"7.0","versionEndExcluding":"7.2"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.19.11"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/2106bf4056858fcce3624e0c51f6fee4d41d3f2f"},{"url":"https://git.kernel.org/stable/c/48fe43666950efefb7ac5fbdc012c1b3604096bf"},{"url":"https://git.kernel.org/stable/c/489291b6b56978cc50d34e8e13f9636ea296ba8a"},{"url":"https://git.kernel.org/stable/c/b0ff6b6ae9c5183ef701ece7016698bde5a5bfba"},{"url":"https://git.kernel.org/stable/c/9ef7dacd44216bf5ea05c8aef49eba4d145f4047"}],"title":"hwmon: (pmbus) Fix passing events to regulator core","x_generator":{"engine":"bippy-1.2.0"}}}}