{"id":"AZL-104360","summary":"CVE-2026-97960 affecting package kernel 6.6.157.1-1","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nperf/x86/intel: Prevent drain_pebs() reentry\n\nThe PEBS buffer is shared by all events on a CPU, so drain_pebs() must\nnot be reentered. If so, one instance may observe stale buffer state and\npotentially access out-of-bound memory.\n\nMost invocations happen in NMI context, which naturally prevents reentry.\nHowever, drain_pebs() is also reachable from process context via\nintel_pmu_drain_pebs_buffer().\n\nIn those paths, the PMU is often already disabled, but not guaranteed.\nFor example, __intel_pmu_pebs_disable() only disables the target counter,\nso other active counters can still raise a PMI and interrupt an in-flight\ndrain_pebs(). Here is an example,\n\n__perf_addr_filters_adjust()\n  perf_event_stop()\n    __perf_event_stop()\n      x86_pmu_stop() (event-\u003epmu-\u003estop)\n        intel_pmu_disable_event()\n          intel_pmu_pebs_disable()\n            __intel_pmu_pebs_disable()\n              intel_pmu_drain_large_pebs()\n                intel_pmu_drain_pebs_buffer()\n\nIntroduce __intel_pmu_quiesce() and __intel_pmu_resume() helpers and\nuse them in intel_pmu_drain_large_pebs() to disable the full PMU\naround the intel_pmu_drain_pebs_buffer() call, preventing reentry.\n\nAlso add a warning in intel_pmu_drain_pebs_buffer() when the full PMU is\nnot disabled.","modified":"2026-09-27T05:34:32Z","published":"2026-09-25T11:17:23Z","upstream":["CVE-2026-97960"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-97960"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"6.6.157.1-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-104360.json"}}],"schema_version":"1.9.0"}