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NVD / CVE Program· CNA Linux

CVE-2021-47006: ARM: 9064/1: hw_breakpoint: Do not directly check the event's overflow_handler hook

Noroxi assessment

Priority: Monitor (action score 22/100)

  • 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: 0.25% (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 3ed8832aeaa9a37b0fc386bb72ff604352567c80, 555a70f7fff03bd669123487905c47ae27dbdaac, 630146203108bf6b8934eec0dfdb3e46dcb917de.
  • Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Low priority for now. Upgrade to Linux Linux 3ed8832aeaa9a37b0fc386bb72ff604352567c80, 555a70f7fff03bd669123487905c47ae27dbdaac, 630146203108bf6b8934eec0dfdb3e46dcb917de 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: ARM: 9064/1: hw_breakpoint: Do not directly check the event's overflow_handler hook The commit 1879445dfa7b ("perf/core: Set event's default ::overflow_handler()") set a default event->overflow_handler in perf_event_alloc(), and replace the check event->overflow_handler with is_default_overflow_handler(), but one is missing. Currently, the bp->overflow_handler can not be NULL. As a result, enable_single_step() is always not invoked. Comments from Zhen Lei: https://patchwork.kernel.org/project/linux-arm-kernel/patch/20210207105934.2001-1-thunder.leizhen@huawei.com/

MediumCVSS 5.5 · v3.1—No exploit Fix available
Published
Feb 28, 2024
Updated
Jun 17, 2026
EPSS
0.2% · 16th percentile
CWE
—

Report tools

JSON

Action score

22

Monitor

Low priority for now.

CVSS
22 / 40 · 5.5 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.2%

CISA SSVC decision

Exploitation
none
Automatable
no
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

Get told when this record changes

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

If any of these changes, we'll tell you in the daily email digest.

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When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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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.

VendorProduct
linuxlinux kernel

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • linux linux kernel4.7 and later · before 4.9.269
  • linux linux kernel4.10 and later · before 4.14.233
  • linux linux kernel4.15 and later · before 4.19.191
  • linux linux kernel4.20 and later · before 5.4.120
  • linux linux kernel5.5 and later · before 5.10.38
  • linux linux kernel5.11 and later · before 5.11.22
  • linux linux kernel5.12 and later · before 5.12.5

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

    • 4.7affected
    • 1879445dfa7bbd6fe21b09c5cc72f4934798afed and later · before 555a70f7fff03bd669123487905c47ae27dbdaacaffected · git
    • 1879445dfa7bbd6fe21b09c5cc72f4934798afed and later · before ed1f67465327cec4457bb988775245b199da86e6affected · git
    • 1879445dfa7bbd6fe21b09c5cc72f4934798afed and later · before a9938d6d78a238d6ab8de57a4d3dcf77adceb9bbaffected · git
    • 1879445dfa7bbd6fe21b09c5cc72f4934798afed and later · before 3ed8832aeaa9a37b0fc386bb72ff604352567c80affected · git
    • 1879445dfa7bbd6fe21b09c5cc72f4934798afed and later · before 630146203108bf6b8934eec0dfdb3e46dcb917deaffected · git
    • 1879445dfa7bbd6fe21b09c5cc72f4934798afed and later · before 7eeacc6728c5478e3c01bc82a1f08958eaa12366affected · git
    • 1879445dfa7bbd6fe21b09c5cc72f4934798afed and later · before dabe299425b1a53a69461fed7ac8922ea6733a25affected · git
    • 1879445dfa7bbd6fe21b09c5cc72f4934798afed and later · before a506bd5756290821a4314f502b4bafc2afcf5260affected · git
    • before 4.7not affected · semver

Package-level exposure

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

EcosystemPackageAffected rangeFix
Debian:12linuxbefore 5.10.38-15.10.38-1
SUSE:Linux Enterprise Real Time 12 SP5kernel-rtbefore 4.12.14-10.182.14.12.14-10.182.1
SUSE:Linux Enterprise Real Time 12 SP5kernel-rt_debugbefore 4.12.14-10.182.14.12.14-10.182.1
SUSE:Linux Enterprise Real Time 12 SP5kernel-source-rtbefore 4.12.14-10.182.14.12.14-10.182.1
SUSE:Linux Enterprise Real Time 12 SP5kernel-syms-rtbefore 4.12.14-10.182.14.12.14-10.182.1

Same product

linux: all records

Other highest-scoring records for the same primary product.

  • CVE-2026-31431crypto: algif_aead - Revert to operating out-of-placeKEV
    90Now
  • CVE-2022-0847A flaw was found in the way the "flags" member of the new pipe buffer structure was lacking proper initialization in copy_page_to_iter_pipe KEV
    89Now
  • CVE-2021-22555Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACEKEV
    85Now

Published before and after this one in the same product

  • ← EarlierCVE-2021-47004Feb 28, 2024 · f2fs: fix to avoid touching checkpointed data in get_victim()
    28Monitor
  • ← EarlierCVE-2021-47005Feb 28, 2024 · PCI: endpoint: Fix NULL pointer dereference for ->get_features()
    22Monitor
  • Later →CVE-2021-47007Feb 28, 2024 · f2fs: fix panic during f2fs_resize_fs()
    22Monitor

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 Linux3ed8832aeaa9a37b0fc386bb72ff604352567c80Vendor (CNA)
Linux Linux555a70f7fff03bd669123487905c47ae27dbdaacVendor (CNA)
Linux Linux630146203108bf6b8934eec0dfdb3e46dcb917deVendor (CNA)
Linux Linux7eeacc6728c5478e3c01bc82a1f08958eaa12366Vendor (CNA)
Linux Linuxa506bd5756290821a4314f502b4bafc2afcf5260Vendor (CNA)
Linux Linuxa9938d6d78a238d6ab8de57a4d3dcf77adceb9bbVendor (CNA)
Linux Linuxdabe299425b1a53a69461fed7ac8922ea6733a25Vendor (CNA)
Linux Linuxed1f67465327cec4457bb988775245b199da86e6Vendor (CNA)
debian:linux5.10.38-1 · Debian:12Package registry (OSV)
suse:kernel-rt4.12.14-10.182.1 · SUSE:Linux Enterprise Real Time 12 SP5Package registry (OSV)
suse:kernel-rt_debug4.12.14-10.182.1 · SUSE:Linux Enterprise Real Time 12 SP5Package registry (OSV)
suse:kernel-source-rt4.12.14-10.182.1 · SUSE:Linux Enterprise Real Time 12 SP5Package registry (OSV)
suse:kernel-syms-rt4.12.14-10.182.1 · SUSE:Linux Enterprise Real Time 12 SP5Package registry (OSV)

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.

No history yet (it accumulates with the daily EPSS job).

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.

No nightly-computed relations.

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).

National notice (Türkiye Cybersecurity Directorate / USOM)

Official security notices citing this record; remediation advice is on the agency's page.

All national notices →

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

Weakness class (CWE)

—

CVSS vector

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

MITRE has no CAPEC/ATT&CK mapping for this CWE.

Change log

  1. Fix✗ → ✓

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

References

Show all references (7 more)

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

All records