CVE-2021-27421Network attack vector

Service crash via SDK_Malloc integer overflow

Published May 3, 2022 · Updated Apr 16, 2025

Integer overflow in NXP MCUXpresso SDK before 2.8.2 allows remote attackers to access out-of-bounds memory through SDK_Malloc. SDK_Malloc performs unchecked integer arithmetic on a particular heap-allocation request, allowing subsequent access beyond the specified array. The affected code must be incorporated into reachable device firmware; triggering it can corrupt memory or crash the device with a segmentation fault.

CVSS severity7.3
High
EPSS probability0.86%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Integer overflow in NXP MCUXpresso SDK before 2.8.2 allows remote attackers to access out-of-bounds memory through SDK_Malloc. SDK_Malloc performs unchecked integer arithmetic on a particular heap-allocation request, allowing subsequent access beyond the specified array. The affected code must be incorporated into reachable device firmware; triggering it can corrupt memory or crash the device with a segmentation fault.

The record

CVE
CVE-2021-27421
Published
May 3, 2022
Updated
Apr 16, 2025
Vendor
NXP Semiconductors
Product
MCUXpresso SDK
Classifications
CWE-190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 3, 2022CVE publishedPublication date reported by the CVE source.
  2. Apr 16, 2025Record 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=unspecified <2.8.2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

NXP Semiconductors · MCUXpresso SDKversion=unspecified <2.8.2

Published CVSS scores

7.5NVDAV:N/AC:L/Au:N/C:P/I:P/A:P
7.3CISA ICS-CERTCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
9.8NVDCVSS:3.1/AV:N/AC:L/PR:N/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.

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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)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-190Integer Overflow or Wraparound

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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