CVE-2021-40154

MEDIUMNVD 6.16.1—Elevated

6.1

NXP LPC55S69 devices before A3 have a buffer over-read via a crafted wlength value in a GET Descriptor Configuration request during use of USB In-System Programming (ISP) mode. This discloses protected flash memory.

CVSS v3: 6.1
EG Score: 6.1(medium)
EPSS: 80.4%
KEV: Not listed

Published

December 1, 2021

Last Modified

November 21, 2024

References (4)

cve@mitrehttps://github.com/Xen1thLabs-AE/CVE-2021-40154
cve@mitrehttps://www.darkmatter.ae/xen1thlabs/published-advisories/
af854a3a-2127-422b-91ae-364da2661108https://github.com/Xen1thLabs-AE/CVE-2021-40154
af854a3a-2127-422b-91ae-364da2661108https://www.darkmatter.ae/xen1thlabs/published-advisories/

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

CWE-125Out-of-bounds Read

Data Freshness Timeline

(refreshed 13× in last 7d / 20× in last 30d)

Every time one of our enrichment pipelines (NVD, MITRE cvelistV5, EPSS, CISA KEV, GHSA, OSV, vendor advisories) ran against this CVE. Most recent first.

2026-06-07 15:23 UTCepss_batch
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Publicly available exploits

(1 reference)

Working exploit code is in the public domain (1 GitHub PoC). Defenders should treat patch urgency accordingly — public PoCs typically lead to mass-exploitation within 24-72 hours.

GitHub PoCJeromeyoung/CVE-2021-40154
First seen Nov 24, 2021
POC to test the BootROM vulnerability found in LPC55S69 and K82 Series
Open source ↗

Frequently asked(5)

What is CVE-2021-40154?

CVE-2021-40154 is a medium vulnerability published on December 1, 2021. NXP LPC55S69 devices before A3 have a buffer over-read via a crafted wlength value in a GET Descriptor Configuration request during use of USB In-System Programming (ISP) mode. This discloses protected flash memory.

When was CVE-2021-40154 disclosed?

CVE-2021-40154 was first published in the National Vulnerability Database on December 1, 2021, with the most recent update on November 21, 2024. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.

Is CVE-2021-40154 actively exploited?

CVE-2021-40154 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 80.4% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.

What is the CVSS score of CVE-2021-40154?

CVE-2021-40154 has a CVSS v3 base score of 6.1 (NVD).

How do I remediate CVE-2021-40154?

Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2021-40154, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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CVE-2021-40154

📅 Published

🔄 Last Modified

🔗 References (4)

Weakness Classification(1)

Data Freshness Timeline

Publicly available exploits

❓ Frequently asked(5)

Dependency Blast Radius

Is Your Infrastructure Affected by CVE-2021-40154?

🔗 Related CVEs(same CWE)

Same CWE

Published

Last Modified

References (4)

Frequently asked(5)

Related CVEs(same CWE)