CVE-2026-40003: CWE-787 Out-of-bounds write in ZTE ZX297520V3 BootROM
The ZTE ZX297520V3 BootROM has an out-of-bounds write vulnerability via USB download mode. This flaw allows attackers to write arbitrary data to any location in the BootROM runtime memory by exploiting the lack of target address validation. Successful exploitation can overwrite the stack, hijack execution flow, bypass Secure Boot signature verification, and execute unauthorized code. The vulnerability affects the 7520V3 chip and has a CVSS score of 5. 1, indicating medium severity. No patch or official remediation has been published yet, and there are no known exploits in the wild.
AI Analysis
Technical Summary
CVE-2026-40003 is a CWE-787 out-of-bounds write vulnerability in the ZTE ZX297520V3 BootROM. The vulnerability arises from insufficient validation of target addresses during USB download mode, enabling arbitrary memory writes. This can lead to stack corruption, control flow hijacking, bypass of Secure Boot signature verification, and unauthorized code execution on affected devices using the 7520V3 chip. The CVSS 3.1 base score is 5.1, reflecting medium severity with attack vector being physical (adjacent) and requiring high attack complexity and user interaction.
Potential Impact
An attacker with physical access to the device's USB interface can exploit this vulnerability to write arbitrary data to BootROM memory. This can compromise the device's Secure Boot mechanism, potentially allowing unauthorized code execution at a low privilege level. The impact includes integrity loss (high), availability impact (low), and confidentiality impact (low). There are no reports of active exploitation in the wild.
Mitigation Recommendations
No official patch or remediation is currently available for this vulnerability. Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is released, limit physical access to affected devices and avoid using USB download mode in untrusted environments.
CVE-2026-40003: CWE-787 Out-of-bounds write in ZTE ZX297520V3 BootROM
Description
The ZTE ZX297520V3 BootROM has an out-of-bounds write vulnerability via USB download mode. This flaw allows attackers to write arbitrary data to any location in the BootROM runtime memory by exploiting the lack of target address validation. Successful exploitation can overwrite the stack, hijack execution flow, bypass Secure Boot signature verification, and execute unauthorized code. The vulnerability affects the 7520V3 chip and has a CVSS score of 5. 1, indicating medium severity. No patch or official remediation has been published yet, and there are no known exploits in the wild.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-40003 is a CWE-787 out-of-bounds write vulnerability in the ZTE ZX297520V3 BootROM. The vulnerability arises from insufficient validation of target addresses during USB download mode, enabling arbitrary memory writes. This can lead to stack corruption, control flow hijacking, bypass of Secure Boot signature verification, and unauthorized code execution on affected devices using the 7520V3 chip. The CVSS 3.1 base score is 5.1, reflecting medium severity with attack vector being physical (adjacent) and requiring high attack complexity and user interaction.
Potential Impact
An attacker with physical access to the device's USB interface can exploit this vulnerability to write arbitrary data to BootROM memory. This can compromise the device's Secure Boot mechanism, potentially allowing unauthorized code execution at a low privilege level. The impact includes integrity loss (high), availability impact (low), and confidentiality impact (low). There are no reports of active exploitation in the wild.
Mitigation Recommendations
No official patch or remediation is currently available for this vulnerability. Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is released, limit physical access to affected devices and avoid using USB download mode in untrusted environments.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- zte
- Date Reserved
- 2026-04-08T07:51:26.675Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 69fbfaa7cbff5d8610569fa2
Added to database: 5/7/2026, 2:36:23 AM
Last enriched: 5/7/2026, 2:51:31 AM
Last updated: 5/7/2026, 3:51:56 AM
Views: 5
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