ZTE ZX297520V3 Signature Verification out-of-bounds write

CVSS Meta Temp Score
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CTI Interest Score
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5.4$0-$5k0.00

Summaryinfo

A vulnerability classified as critical has been found in ZTE ZX297520V3 7520V3. This affects an unknown part of the component Signature Verification. This manipulation causes out-of-bounds write. The identification of this vulnerability is CVE-2026-40003. It is feasible to perform the attack on the physical device. There is no exploit available.

Detailsinfo

A vulnerability has been found in ZTE ZX297520V3 7520V3 and classified as critical. Affected by this vulnerability is some unknown processing of the component Signature Verification. The manipulation with an unknown input leads to a out-of-bounds write vulnerability. The CWE definition for the vulnerability is CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

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.

The weakness was shared by rva3. It is possible to read the advisory at support.zte.com.cn. This vulnerability is known as CVE-2026-40003 since 04/08/2026. The exploitation appears to be easy. Attacking locally is a requirement. The exploitation doesn't need any form of authentication. The technical details are unknown and an exploit is not publicly available.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at CNNVD (CNNVD-202605-1453). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Vendor

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Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.4
VulDB Meta Temp Score: 5.4

VulDB Base Score: 4.3
VulDB Temp Score: 4.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 6.8
NVD Vector: 🔒

CNA Base Score: 5.1
CNA Vector (zte): 🔒

CVSSv2info

AVACAuCIA
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Out-of-bounds write
CWE: CWE-787 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: Yes
Local: Yes
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

04/08/2026 CVE reserved
05/07/2026 +29 days Advisory disclosed
05/07/2026 +0 days VulDB entry created
05/17/2026 +10 days VulDB entry last update

Sourcesinfo

Vendor: zte.com.cn

Advisory: support.zte.com.cn
Researcher: rva3
Status: Confirmed

CVE: CVE-2026-40003 (🔒)
GCVE (CVE): GCVE-0-2026-40003
GCVE (VulDB): GCVE-100-361759
CNNVD: CNNVD-202605-1453 - ZTE ZX297520V3 缓冲区错误漏洞

Entryinfo

Created: 05/07/2026 07:24
Updated: 05/17/2026 16:59
Changes: 05/07/2026 07:24 (63), 05/08/2026 20:07 (6), 05/17/2026 16:59 (11)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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