CVE-2021-47022

Kernel memory exhaustion via leaked mt7615 TX tokens

Published Feb 28, 2024 · Updated May 23, 2026

Memory leak in the Linux kernel mt7615 driver allows local users to exhaust memory during device teardown in affected versions. mt7615_unregister_device() frees pending TXWI entries before mt7615_tx_token_put() releases their associated TX tokens, leaving allocated memory unreclaimed. NVD assesses low-privileged local access and availability impact only; upstream does not identify the exact user action that reaches teardown.

CVSS severity5.5
Medium
EPSS probability0.24%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Memory leak in the Linux kernel mt7615 driver allows local users to exhaust memory during device teardown in affected versions. mt7615_unregister_device() frees pending TXWI entries before mt7615_tx_token_put() releases their associated TX tokens, leaving allocated memory unreclaimed. NVD assesses low-privileged local access and availability impact only; upstream does not identify the exact user action that reaches teardown.

The record

CVE
CVE-2021-47022
Published
Feb 28, 2024
Updated
May 23, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
CWE-401, T1499
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 28, 2024CVE publishedPublication date reported by the CVE source.
  2. May 23, 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=1aca6c30d4b655a4fd29c4ad66985b60def88eed <107bcbb219ac84d885ac63b25246f8d33212bc47
  2. Affected versionversion=5.10.21 <5.10.37
  3. Affected versionversion=5.11.4 <5.11.21
  4. Affected versionversion=5.12
  5. Affected versionversion=a6275e934605646ef81b02d8d1164f21343149c9 <6c5b2b0c6e5a6ce2d8f9f85b8b72bfad60eaa506
  6. Affected versionversion=a6275e934605646ef81b02d8d1164f21343149c9 <8ab31da7b89f71c4c2defcca989fab7b42f87d71
  7. Affected versionversion=aec5719681405af21102c2407b01f83ed19e9833 <4fa28c807da54c1d720b3cc12e48eb9bea1e2c8f

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=1aca6c30d4b655a4fd29c4ad66985b60def88eed <107bcbb219ac84d885ac63b25246f8d33212bc47; version=5.10.21 <5.10.37; version=5.11.4 <5.11.21; version=5.12; version=a6275e934605646ef81b02d8d1164f21343149c9 <6c5b2b0c6e5a6ce2d8f9f85b8b72bfad60eaa506; version=a6275e934605646ef81b02d8d1164f21343149c9 <8ab31da7b89f71c4c2defcca989fab7b42f87d71; version=aec5719681405af21102c2407b01f83ed19e9833 <4fa28c807da54c1d720b3cc12e48eb9bea1e2c8f

Published CVSS scores

5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/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.

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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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-401Missing Release of Memory after Effective Lifetime
T1499Endpoint Denial of Service

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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