HOMEVULNERABILITIESCVE-2026-40003
MEDIUM

CVE-2026-40003

CWE-787Published: May 7, 2026· Updated: May 13, 2026

6.8
CVSS v3.1
EPSS:0.02%probability of exploitation in 30 daysPercentile:4.3th

Official Description

ZTE ZX297520V3 BootROM contains a vulnerability that allows arbitrary memory writes via USB. Attackers can exploit the lack of target address validation in the USB download mode to write data to any location in BootROM runtime memory, thereby overwriting the stack, hijacking the execution flow, bypassing the Secure Boot signature verification mechanism, and achieving unauthorized code execution.

NVD Source

Technical Analysis

CVE-2026-40003 requires local access, meaning attackers must already have a foothold on the target system.

The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.

A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 6.8.

From a weakness classification perspective (CWE-787): Out-of-bounds write vulnerabilities can lead to data corruption, crashes, or arbitrary code execution.

CVSS v3.1 Vector Breakdown

Exploitability
Attack VectorPhysical
Attack ComplexityLow
Privileges Req.None
User InteractionNone
ScopeUnchanged
Impact
ConfidentialityHigh
IntegrityHigh
AvailabilityHigh
CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected Vendors & Products

zte2 products
zx297520v3 firmwarezx297520v3
Source: NVD CPE · 2 total CPE entries

Exploit & PoC Resources

NO KNOWN EXPLOITNo public exploit confirmed at this time
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Official Patches & Advisories

All References (1)

Quick Facts

CVE IDCVE-2026-40003
CVSS Score6.8 / 10
SeverityMEDIUM
WeaknessCWE-787
CISA KEVNo
EPSS (30d)0.02%
Affected1 vendor
PublishedMay 7, 2026

Related CVEs (CWE-787)

Recommended Actions

  • Apply vendor patches immediately
  • Monitor CVE-2026-40003 in threat intel feeds
  • Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWATCH.COM. CVE data is provided under the NVD usage policy.
CVE-2026-40003 — CVSS 6.8 MEDIUM | CTIWATCH.COM