CVE-2025-9791: ac20 Buffer Overflow — Exploit

Description

A weakness has been identified in Tenda AC20 16.03.08.05. This vulnerability affects unknown code of the file /goform/fromAdvSetMacMtuWan. This manipulation of the argument wanMTU causes stack-based buffer overflow. Remote exploitation of the attack is possible. The exploit has been made available to the public and could be exploited.

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CVSS v3.1 Score

8.8

HIGH

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Weakness Type (CWE)

CWE-119 Buffer Overflow

CWE-121 CWE-121

CWE-787 Out-of-bounds Write

Affected Products

Vendor	Product	Versions
tenda	ac20_firmware	All
tenda	ac20	All

References

Exploits

https://github.com/Cpppq43/Tenda/blob/main/Tenda_AC20_V16.03.08.05.md https://github.com/Cpppq43/Tenda/blob/main/Tenda_AC20_V16.03.08.05.md#poc https://github.com/Cpppq43/Tenda/blob/main/Tenda_AC20_V16.03.08.05.md https://github.com/Cpppq43/Tenda/blob/main/Tenda_AC20_V16.03.08.05.md#poc

Other References

https://vuldb.com/?ctiid.322106 https://vuldb.com/?id.322106 https://vuldb.com/?submit.641088 https://www.tenda.com.cn/

Frequently Asked Questions

What is CVE-2025-9791? +

A weakness has been identified in Tenda AC20 16.03.08.05. This vulnerability affects unknown code of the file /goform/fromAdvSetMacMtuWan. This manipulation of the argument wanMTU causes stack-based buffer overflow. Remote exploitation of the attack is possible. The exploit has been made available to the public and could be exploited. It has a CVSS v3.1 base score of 8.8 (HIGH).

How severe is CVE-2025-9791? +

CVE-2025-9791 has a CVSS v3.1 score of 8.8 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

What products are affected by CVE-2025-9791? +

CVE-2025-9791 affects products from tenda, specifically: ac20, ac20_firmware. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-9791? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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