CVE-2021-47314

Kernel memory exhaustion via leaked probe allocation

Published May 21, 2024 · Updated May 11, 2026

A memory leak in the fsl_ifc driver in Linux allows local users to exhaust kernel memory during failed device probing. The fsl_ifc_ctrl_probe function allocates its private controller structure with kzalloc but returns from probe-error paths without freeing that allocation. Triggering is limited to systems with CONFIG_FSL_IFC and requires CAP_SYS_ADMIN; repeated failures consume memory and can interrupt service.

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

A memory leak in the fsl_ifc driver in Linux allows local users to exhaust kernel memory during failed device probing. The fsl_ifc_ctrl_probe function allocates its private controller structure with kzalloc but returns from probe-error paths without freeing that allocation. Triggering is limited to systems with CONFIG_FSL_IFC and requires CAP_SYS_ADMIN; repeated failures consume memory and can interrupt service.

The record

CVE
CVE-2021-47314
Published
May 21, 2024
Updated
May 11, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
CWE-401, T1499.004
Attack vector
local
Privileges
admin

Timeline

How it unfolded

  1. May 21, 2024CVE publishedPublication date reported by the CVE source.
  2. May 11, 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=3.3
  2. Affected versionversion=a20cbdeffce247a2b6fb83cd8d22433994068565 <3b45b8a7d549bd92ec94b5357c2c2c1a7ed107e4
  3. Affected versionversion=a20cbdeffce247a2b6fb83cd8d22433994068565 <443f6ca6fd186b4fa4e6f377b6e19a91feb1a0d5
  4. Affected versionversion=a20cbdeffce247a2b6fb83cd8d22433994068565 <48ee69825f7480622ed447b0249123236d3b3ad0
  5. Affected versionversion=a20cbdeffce247a2b6fb83cd8d22433994068565 <7626ffbea708e5aba6912295c012d2b409a1769f
  6. Affected versionversion=a20cbdeffce247a2b6fb83cd8d22433994068565 <8018476756066e97ecb886c3dc024aeb7d5792ad
  7. Affected versionversion=a20cbdeffce247a2b6fb83cd8d22433994068565 <8e0d09b1232d0538066c40ed4c13086faccbdff6
  8. Affected versionversion=a20cbdeffce247a2b6fb83cd8d22433994068565 <a6b45b4932f7b0c36b41fb56a35ad679ece939a0
  9. Affected versionversion=a20cbdeffce247a2b6fb83cd8d22433994068565 <b5789e23773f4a852fbfe244b63f675e265d3a7f
  10. Affected versionversion=a20cbdeffce247a2b6fb83cd8d22433994068565 <ee1aa737ba0b75ab8af3444c4ae5bdba36aed6e6

What conditions does exploitation require?

Attack vectorlocal
Required privilegesadmin

What is affected?

The Linux Kernel Organization · Linuxversion=3.3; version=a20cbdeffce247a2b6fb83cd8d22433994068565 <3b45b8a7d549bd92ec94b5357c2c2c1a7ed107e4; version=a20cbdeffce247a2b6fb83cd8d22433994068565 <443f6ca6fd186b4fa4e6f377b6e19a91feb1a0d5; version=a20cbdeffce247a2b6fb83cd8d22433994068565 <48ee69825f7480622ed447b0249123236d3b3ad0; version=a20cbdeffce247a2b6fb83cd8d22433994068565 <7626ffbea708e5aba6912295c012d2b409a1769f; version=a20cbdeffce247a2b6fb83cd8d22433994068565 <8018476756066e97ecb886c3dc024aeb7d5792ad; version=a20cbdeffce247a2b6fb83cd8d22433994068565 <8e0d09b1232d0538066c40ed4c13086faccbdff6; version=a20cbdeffce247a2b6fb83cd8d22433994068565 <a6b45b4932f7b0c36b41fb56a35ad679ece939a0; version=a20cbdeffce247a2b6fb83cd8d22433994068565 <b5789e23773f4a852fbfe244b63f675e265d3a7f; version=a20cbdeffce247a2b6fb83cd8d22433994068565 <ee1aa737ba0b75ab8af3444c4ae5bdba36aed6e6

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
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-401Missing Release of Memory after Effective Lifetime
T1499.004Endpoint Denial of Service: Application 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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