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NVD / CVE Program· CNA Linux

CVE-2026-64556: perf/core: Detach event groups during remove_on_exec

Noroxi assessment

Priority: Monitor (action score 31/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.16% (FIRST EPSS).
  • Someone with local access to the system can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: Linux Linux 037a3c43edfb597665dd34457cd22b14692f2ba3, 06ccef0434e98058ddae7bcebc901f93d22b7653, 1d3e1102273f09180262496658e7eeed8a5a7b59; azl3 kernel 6.6.144.1-1 on Azure Linux 3.0 6.6.145.2-1.

Low priority for now. Upgrade to Linux Linux 037a3c43edfb597665dd34457cd22b14692f2ba3, 06ccef0434e98058ddae7bcebc901f93d22b7653, 1d3e1102273f09180262496658e7eeed8a5a7b59; azl3 kernel 6.6.144.1-1 on Azure Linux 3.0 6.6.145.2-1 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

In the Linux kernel, the following vulnerability has been resolved: perf/core: Detach event groups during remove_on_exec perf_event_remove_on_exec() removes events by calling perf_event_exit_event(). For top-level events, this removes the event from the context with DETACH_EXIT only. This can leave inconsistent group state when a removed event is a group leader and the group contains siblings without remove_on_exec. If the group was active, the surviving siblings can remain active and attached to the removed leader's sibling list, but are no longer represented by a valid group leader on the PMU context active lists. A later close of the removed leader uses DETACH_GROUP and can promote the still-active siblings from this stale group state. The next schedule-in can then add an already-linked active_list entry again, corrupting the PMU context active list. With DEBUG_LIST enabled, this is caught as a list_add double-add in merge_sched_in(). Fix this by detaching group relationships when remove_on_exec removes an event. This preserves the existing task-exit and revoke behavior, while ensuring surviving siblings are ungrouped before the removed event leaves the context.

HighCVSS 7.8 · v3.1—No exploit Fix available
Published
Jul 29, 2026
Updated
Nov 3, 2026
EPSS
0.1% · 5th percentile

Report tools

JSON

Action score

31

Monitor

Low priority for now.

CVSS
31 / 40 · 7.8 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.1%

CISA SSVC decision

Exploitation
none
Automatable
no
Technical impact
total

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
—
CNA · Linux
7.8
NVD has not scored this yet; the score shown is the CNA’s.

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

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  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

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Noroxi analysis

What does it mean in your environment?

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

—

Versions reported by the vendor

Affected version ranges reported by the assigning authority (Linux). Independent of NVD's CPE analysis and usually ahead of it.

  • Linux Linux

    • 5.13affected
    • 2e498d0a74e5b88a6689ae1b811f247f91ff188e and later · before 1d3e1102273f09180262496658e7eeed8a5a7b59affected · git
    • 2e498d0a74e5b88a6689ae1b811f247f91ff188e and later · before 4cdb1b3ab96eb1b7eb70bc5c82fede334bd60df2affected · git
    • 2e498d0a74e5b88a6689ae1b811f247f91ff188e and later · before 39358e856fb89e62e3c8d7389a2dc4ec33dbe90eaffected · git
    • 2e498d0a74e5b88a6689ae1b811f247f91ff188e and later · before a2d5d3ee7b6e3953114726b1521e62123ab5b043affected · git
    • 2e498d0a74e5b88a6689ae1b811f247f91ff188e and later · before 06ccef0434e98058ddae7bcebc901f93d22b7653affected · git
    • 2e498d0a74e5b88a6689ae1b811f247f91ff188e and later · before 037a3c43edfb597665dd34457cd22b14692f2ba3affected · git
    • before 5.13not affected · semver
    • 6.1.191 and later · up to and including 6.1.*not affected · semver
    • 6.6.145 and later · up to and including 6.6.*not affected · semver

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
AlmaLinux:10kernelbefore 6.12.0-211.61.1.el10_26.12.0-211.61.1.el10_2
AlmaLinux:10kernel-64kbefore 6.12.0-211.61.1.el10_26.12.0-211.61.1.el10_2
AlmaLinux:10kernel-64k-corebefore 6.12.0-211.61.1.el10_26.12.0-211.61.1.el10_2
AlmaLinux:10kernel-64k-debugbefore 6.12.0-211.61.1.el10_26.12.0-211.61.1.el10_2
AlmaLinux:10kernel-64k-debug-corebefore 6.12.0-211.61.1.el10_26.12.0-211.61.1.el10_2
AlmaLinux:10kernel-64k-debug-develbefore 6.12.0-211.61.1.el10_26.12.0-211.61.1.el10_2
AlmaLinux:10kernel-64k-debug-devel-matchedbefore 6.12.0-211.61.1.el10_26.12.0-211.61.1.el10_2
AlmaLinux:10kernel-64k-debug-modulesbefore 6.12.0-211.61.1.el10_26.12.0-211.61.1.el10_2
AlmaLinux:10kernel-64k-debug-modules-corebefore 6.12.0-211.61.1.el10_26.12.0-211.61.1.el10_2
AlmaLinux:10kernel-64k-debug-modules-extrabefore 6.12.0-211.61.1.el10_26.12.0-211.61.1.el10_2
AlmaLinux:10kernel-64k-develbefore 6.12.0-211.61.1.el10_26.12.0-211.61.1.el10_2
AlmaLinux:10kernel-64k-devel-matchedbefore 6.12.0-211.61.1.el10_26.12.0-211.61.1.el10_2
AlmaLinux:10kernel-64k-modulesbefore 6.12.0-211.61.1.el10_26.12.0-211.61.1.el10_2
AlmaLinux:10kernel-64k-modules-corebefore 6.12.0-211.61.1.el10_26.12.0-211.61.1.el10_2
AlmaLinux:10kernel-64k-modules-extrabefore 6.12.0-211.61.1.el10_26.12.0-211.61.1.el10_2
AlmaLinux:10kernel-abi-stablelistsbefore 6.12.0-211.61.1.el10_26.12.0-211.61.1.el10_2
AlmaLinux:10kernel-corebefore 6.12.0-211.61.1.el10_26.12.0-211.61.1.el10_2
AlmaLinux:10kernel-cross-headersbefore 6.12.0-211.61.1.el10_26.12.0-211.61.1.el10_2
AlmaLinux:10kernel-debugbefore 6.12.0-211.61.1.el10_26.12.0-211.61.1.el10_2
AlmaLinux:10kernel-debug-corebefore 6.12.0-211.61.1.el10_26.12.0-211.61.1.el10_2
AlmaLinux:10kernel-debug-develbefore 6.12.0-211.61.1.el10_26.12.0-211.61.1.el10_2
AlmaLinux:10kernel-debug-devel-matchedbefore 6.12.0-211.61.1.el10_26.12.0-211.61.1.el10_2
AlmaLinux:10kernel-debug-modulesbefore 6.12.0-211.61.1.el10_26.12.0-211.61.1.el10_2
AlmaLinux:10kernel-debug-modules-corebefore 6.12.0-211.61.1.el10_26.12.0-211.61.1.el10_2

+96

Same product

linux: all records

Other highest-scoring records for the same primary product.

  • CVE-2026-74705udp: fix potential use-after-free in tunnel segmentation
    40Plan
  • CVE-2026-74612veth: fix skb length accounting after XDP frag adjustment
    40Plan
  • CVE-2026-74475vxlan: use neigh_ha_snapshot() in route_shortcircuit()
    40Plan

Published before and after this one in the same product

  • ← EarlierCVE-2026-64554Jul 27, 2026 · netfilter: bridge: fix stale prevhdr pointer in br_ip6_fragment()
    35Monitor
  • ← EarlierCVE-2026-64555Jul 27, 2026 · KVM: arm64: nv: Fix SPSR_EL2 restore in kvm_hyp_handle_mops()
    35Monitor
  • Later →CVE-2026-64557Jul 29, 2026 · Bluetooth: L2CAP: Fix use-after-free in l2cap_sock_new_connection_cb()
    35Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
Linux Linux037a3c43edfb597665dd34457cd22b14692f2ba3Vendor (CNA)
Linux Linux06ccef0434e98058ddae7bcebc901f93d22b7653Vendor (CNA)
Linux Linux1d3e1102273f09180262496658e7eeed8a5a7b59Vendor (CNA)
Linux Linux39358e856fb89e62e3c8d7389a2dc4ec33dbe90eVendor (CNA)
Linux Linux4cdb1b3ab96eb1b7eb70bc5c82fede334bd60df2Vendor (CNA)
Linux Linuxa2d5d3ee7b6e3953114726b1521e62123ab5b043Vendor (CNA)
azl3 kernel 6.6.144.1-1 on Azure Linux 3.06.6.145.2-1 · CBL-Mariner ReleasesMicrosoft (MSRC)
almalinux:bpftool4.18.0-553.169.1.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel4.18.0-553.169.1.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt4.18.0-553.169.1.rt7.510.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-core4.18.0-553.169.1.rt7.510.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-debug4.18.0-553.169.1.rt7.510.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-debug-core4.18.0-553.169.1.rt7.510.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-debug-devel4.18.0-553.169.1.rt7.510.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-debug-modules4.18.0-553.169.1.rt7.510.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-debug-modules-extra4.18.0-553.169.1.rt7.510.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-devel4.18.0-553.169.1.rt7.510.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-modules4.18.0-553.169.1.rt7.510.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-modules-extra4.18.0-553.169.1.rt7.510.el8_10 · AlmaLinux:8Package registry (OSV)
debian:linux6.12.96-1 · Debian:13Package registry (OSV)
debian:linux-6.126.12.100-1~deb12u1 · Debian:12Package registry (OSV)
red hat:kernel-rt0:4.18.0-553.169.1.rt7.510.el8_10 · Red Hat:enterprise_linux:8::nfvPackage registry (OSV)
red hat:kernel-rt-core0:4.18.0-553.169.1.rt7.510.el8_10 · Red Hat:enterprise_linux:8::nfvPackage registry (OSV)
red hat:kernel-rt-debug0:4.18.0-553.169.1.rt7.510.el8_10 · Red Hat:enterprise_linux:8::nfvPackage registry (OSV)
red hat:kernel-rt-debug-core0:4.18.0-553.169.1.rt7.510.el8_10 · Red Hat:enterprise_linux:8::nfvPackage registry (OSV)
red hat:kernel-rt-debug-debuginfo0:4.18.0-553.169.1.rt7.510.el8_10 · Red Hat:enterprise_linux:8::nfvPackage registry (OSV)
red hat:kernel-rt-debug-devel0:4.18.0-553.169.1.rt7.510.el8_10 · Red Hat:enterprise_linux:8::nfvPackage registry (OSV)
red hat:kernel-rt-debug-kvm0:4.18.0-553.169.1.rt7.510.el8_10 · Red Hat:enterprise_linux:8::nfvPackage registry (OSV)
red hat:kernel-rt-debug-modules0:4.18.0-553.169.1.rt7.510.el8_10 · Red Hat:enterprise_linux:8::nfvPackage registry (OSV)
red hat:kernel-rt-debug-modules-extra0:4.18.0-553.169.1.rt7.510.el8_10 · Red Hat:enterprise_linux:8::nfvPackage registry (OSV)

+17

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

  • CVE-2025-68775197 days apartnet/handshake: duplicate handshake cancellations leak socket
    39Monitor
  • CVE-2026-6814912 days apartfs: preserve ACL_DONT_CACHE state in forget_cached_acl()
    33Monitor
  • CVE-2026-7205717 days apartnet/sched: act_ct: preserve tc_skb_cb across defragmentation
    32Monitor
  • CVE-2026-6840412 days apartwifi: cfg80211: use wiphy work for socket owner autodisconnect
    31Monitor
  • CVE-2026-6810312 days apartdrm/amdgpu: reject mapping a reserved doorbell to a new queue
    28Monitor

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

  • Someone with local access to the system can trigger it.
  • A low-privileged account is enough.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
high · data can be read
Integrity
high · data or configuration can be modified
Availability
high · the service can be disrupted
Attack vector
Local
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality impact
High
Integrity impact
High
Availability impact
High

Weakness class (CWE)

CWE-662 · Improper Synchronization

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

nvd-secondary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

Change log

  1. SSVC exploitation— → none
  2. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Show all references (5 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records