CVE-2021-47069

Kernel compromise via IPC stack use-after-free

Published Mar 1, 2024 · Updated Aug 5, 2026

Stack use-after-free in Linux 5.6 through 5.10.39, 5.11 through 5.12.6, and 5.13-rc1 through 5.13-rc2 allows local users to crash the kernel. __pipelined_op sets STATE_READY and then dereferences an ext_wait_queue on the receiver's expired stack, passing a bogus task_struct to wake_q_add_safe. An unprivileged local user controls both sides of the IPC race; successful reuse permits kernel-memory disclosure, writes, control-flow hijacking, or a panic.

CVSS severity7.0
High
EPSS probability0.26%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stack use-after-free in Linux 5.6 through 5.10.39, 5.11 through 5.12.6, and 5.13-rc1 through 5.13-rc2 allows local users to crash the kernel. __pipelined_op sets STATE_READY and then dereferences an ext_wait_queue on the receiver's expired stack, passing a bogus task_struct to wake_q_add_safe. An unprivileged local user controls both sides of the IPC race; successful reuse permits kernel-memory disclosure, writes, control-flow hijacking, or a panic.

The record

CVE
CVE-2021-47069
Published
Mar 1, 2024
Updated
Aug 5, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
T1499.004
Attack vector
local
Privileges
Unavailable

Timeline

How it unfolded

  1. Mar 1, 2024CVE publishedPublication date reported by the CVE source.
  2. Aug 5, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=5.6
  2. Affected versionversion=c5b2cbdbdac563f46ecd5e187253ab1abbd6fc04 <4528c0c323085e645b8765913b4a7fd42cf49b65
  3. Affected versionversion=c5b2cbdbdac563f46ecd5e187253ab1abbd6fc04 <807fa14536b26803b858da878b643be72952a097
  4. Affected versionversion=c5b2cbdbdac563f46ecd5e187253ab1abbd6fc04 <a11ddb37bf367e6b5239b95ca759e5389bb46048

What conditions does exploitation require?

Attack vectorlocal
Required privilegesUnavailable in this record.

What is affected?

The Linux Kernel Organization · Linuxversion=5.6; version=c5b2cbdbdac563f46ecd5e187253ab1abbd6fc04 <4528c0c323085e645b8765913b4a7fd42cf49b65; version=c5b2cbdbdac563f46ecd5e187253ab1abbd6fc04 <807fa14536b26803b858da878b643be72952a097; version=c5b2cbdbdac563f46ecd5e187253ab1abbd6fc04 <a11ddb37bf367e6b5239b95ca759e5389bb46048

Published CVSS scores

7.0CanonicalCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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