{
  "threat_severity" : "Moderate",
  "public_date" : "2026-04-22T00:00:00Z",
  "bugzilla" : {
    "description" : "kernel: perf: Make sure to use pmu_ctx->pmu for groups",
    "id" : "2460668",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2460668"
  },
  "cvss3" : {
    "cvss3_base_score" : "5.5",
    "cvss3_scoring_vector" : "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
    "status" : "draft"
  },
  "cwe" : "CWE-787",
  "details" : [ "In the Linux kernel, the following vulnerability has been resolved:\nperf: Make sure to use pmu_ctx->pmu for groups\nOliver reported that x86_pmu_del() ended up doing an out-of-bound memory access\nwhen group_sched_in() fails and needs to roll back.\nThis *should* be handled by the transaction callbacks, but he found that when\nthe group leader is a software event, the transaction handlers of the wrong PMU\nare used. Despite the move_group case in perf_event_open() and group_sched_in()\nusing pmu_ctx->pmu.\nTurns out, inherit uses event->pmu to clone the events, effectively undoing the\nmove_group case for all inherited contexts. Fix this by also making inherit use\npmu_ctx->pmu, ensuring all inherited counters end up in the same pmu context.\nSimilarly, __perf_event_read() should use equally use pmu_ctx->pmu for the\ngroup case.", "A flaw was found in the Linux kernel's performance monitoring unit (PMU) subsystem. This vulnerability occurs when handling performance event groups, specifically during the rollback of `group_sched_in()` operations. An issue with how inherited contexts use event pointers can lead to an out-of-bounds memory access. This could allow a local attacker to cause a denial of service or potentially escalate privileges." ],
  "statement" : "Upstream ensures inherited and grouped perf events consistently use `pmu_ctx->pmu`, preventing rollback paths from touching the wrong PMU's transaction state when the group leader is software-defined. Red Hat recommends patched kernels for perf-heavy workloads. Unloading `kvm_intel`/`kvm_amd` is unrelated; perf is core.",
  "package_state" : [ {
    "product_name" : "Red Hat Enterprise Linux 10",
    "fix_state" : "Fix deferred",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:10"
  }, {
    "product_name" : "Red Hat Enterprise Linux 6",
    "fix_state" : "Not affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:6"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Fix deferred",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Fix deferred",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "fix_state" : "Fix deferred",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "fix_state" : "Fix deferred",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Fix deferred",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Fix deferred",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  } ],
  "references" : [ "https://www.cve.org/CVERecord?id=CVE-2026-31528\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-31528\nhttps://lore.kernel.org/linux-cve-announce/2026042214-CVE-2026-31528-b375@gregkh/T" ],
  "name" : "CVE-2026-31528",
  "csaw" : false
}