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VulnerabilityPublished Updated

CVE-2026-97960: Linux kernel · perf/x86/intel: Prevent drain_pebs() reentry

Affects Linux kernelSource CVE Database V5

0

Not known to be exploited · fixed in c55599c0ec2aa020e41a0599c3044c56d8a2e7d9 : update Linux kernel when convenient.

Data as of 26 Oct 2026, 13:47 UTC

Severity
Unrated

Rated by Threat Radar · CVSS not yet scored by NVD

EPSS
0.1% chance of exploitation in 30 days – higher than 6% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch
Available – fixed in c55599c0ec2aa020e41a0599c3044c56d8a2e7d9, a56c03a397e2cd0c4cf8da96dcd6214f7d0e7d8c, a5fe19dd8b3ed5fad6e5e0f0c58c7245043ee4af +3

Exploitation evidence

  1. Disclosed: evidence found.

    CVE published 25 Sep 2026

  2. Detectable: no evidence on record.

    No public nuclei template indexed

  3. Weaponised: no evidence on record.

    No public exploit code indexed in Metasploit or Exploit-DB

  4. Exploited in the wild: no evidence on record.

    Not in CISA KEV and no source reports exploitation

  5. Observed by OffSeq Mirage: no evidence on record.

    No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

What to do

Upgrade to a fixed release listed under Affected software.

Affected software

ProductAffectedFixed in
LinuxLinuxAffected
  • >=6.3.7 <6.4
Fixed in
  • c55599c0ec2aa020e41a0599c3044c56d8a2e7d9
  • a56c03a397e2cd0c4cf8da96dcd6214f7d0e7d8c
  • a5fe19dd8b3ed5fad6e5e0f0c58c7245043ee4af
  • 9882068ed242fcd4743f53027e8c790e88dcafff
  • 999e482fdf89400cc1ae937680fc05096b4c915b
  • 6.4
LinuxLinuxAffected
  • =6.4
Fixed in–

Description

In the Linux kernel, the following vulnerability has been resolved: perf/x86/intel: Prevent drain_pebs() reentry The PEBS buffer is shared by all events on a CPU, so drain_pebs() must not be reentered. If so, one instance may observe stale buffer state and potentially access out-of-bound memory. Most invocations happen in NMI context, which naturally prevents reentry. However, drain_pebs() is also reachable from process context via intel_pmu_drain_pebs_buffer(). In those paths, the PMU is often already disabled, but not guaranteed. For example, __intel_pmu_pebs_disable() only disables the target counter, so other active counters can still raise a PMI and interrupt an in-flight drain_pebs(). Here is an example, __perf_addr_filters_adjust() perf_event_stop() __perf_event_stop() x86_pmu_stop() (event->pmu->stop) intel_pmu_disable_event() intel_pmu_pebs_disable() __intel_pmu_pebs_disable() intel_pmu_drain_large_pebs() intel_pmu_drain_pebs_buffer() Introduce __intel_pmu_quiesce() and __intel_pmu_resume() helpers and use them in intel_pmu_drain_large_pebs() to disable the full PMU around the intel_pmu_drain_pebs_buffer() call, preventing reentry. Also add a warning in intel_pmu_drain_pebs_buffer() when the full PMU is not disabled.

References

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