CVE-2021-31532: NXP LPC55S6x microcontrollers (0A and 1B), i.MX RT500 (silicon rev B1 and B2), i.MX RT600 (silicon rev A0, B0)

Routine

MEDIUM 6.8MITIGATEMITIGATEMITIGATE

CVE-2021-31532 is a medium-severity flaw (CVSS 6.8) affecting lpc55s69jbd100 firmware, lpc55s66jbd100 firmware, lpc55s69jev98 firmware. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

NXP LPC55S6x microcontrollers (0A and 1B), i.MX RT500 (silicon rev B1 and B2), i.MX RT600 (silicon rev A0, B0), LPC55S6x, LPC55S2x, LPC552x (silicon rev 0A, 1B), LPC55S1x, LPC551x (silicon rev 0A) and LPC55S0x, LPC550x (silicon rev 0A) include an undocumented ROM patch peripheral that allows unsigned, non-persistent modification of the internal ROM.

Why this priority

Public exploit reference

No fix is published yet: follow the downgrade or mitigation steps.

Risk facts

CVSS score	6.8 (Medium)
Attack vector	Physical
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	0.5% (top 61%)
CISA exploited list	No
Published	2021-05-06
Last modified	2026-06-17

Publisher (CNA): MITRE · Vendor: nxp

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2021-05-06 13:15 UTCPublished CVE record published
2026-06-17 03:51 UTCUpdated Record last modified

nxp lpc55s69jbd100 firmware MITIGATE

Affected: all versions

Fixed in: no fixed release known

Safe to downgrade to: no unaffected older release

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

nxp lpc55s66jbd100 firmware MITIGATE

Affected: all versions

Fixed in: no fixed release known

Safe to downgrade to: no unaffected older release

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

nxp lpc55s69jev98 firmware MITIGATE

Affected: all versions

Fixed in: no fixed release known

Safe to downgrade to: no unaffected older release

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

nxp lpcs66jev98 firmware MITIGATE

Affected: all versions

Fixed in: no fixed release known

Safe to downgrade to: no unaffected older release

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

nxp lpc55s69jbd64 firmware MITIGATE

Affected: all versions

Fixed in: no fixed release known

Safe to downgrade to: no unaffected older release

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

nxp lpcs66jbd64 firmware MITIGATE

Affected: all versions

Fixed in: no fixed release known

Safe to downgrade to: no unaffected older release

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2021-31532?

lpc55s69jbd100 firmware: mitigate or apply the listed mitigation; lpc55s66jbd100 firmware: mitigate or apply the listed mitigation; lpc55s69jev98 firmware: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2021-31532 being exploited?

CVE-2021-31532 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2021-31532 affect?

CVE-2021-31532 affects lpc55s69jbd100 firmware, lpc55s66jbd100 firmware, lpc55s69jev98 firmware. Severity is medium (CVSS 6.8). NXP LPC55S6x microcontrollers (0A and 1B), i.MX RT500 (silicon rev B1 and B2), i.MX RT600 (silicon rev A0, B0), LPC55S6x, LPC55S2x, LPC552x (silicon rev 0A, 1B), LPC55S1x, LPC551x (silicon rev 0A) and LPC55S0x, LPC550x (silicon rev 0A) incl

How urgent is CVE-2021-31532?

Priority 39/100. Public exploit reference

Related CVEs

CVE-2022-22819 HIGH 7.8 MITIGATE MITIGATE NXP LPC55S66JBD64, LPC55S66JBD100, LPC55S66JEV98, LPC55S69JBD64, LPC55S69JBD100, and LPC55S69JEV98 microcontro
CVE-2021-40154 MEDIUM 6.1 MITIGATE MITIGATE NXP LPC55S69 devices before A3 have a buffer over-read via a crafted wlength value in a GET Descriptor Configu

References

← Back to latest CVEs