CVE-2025-8939: Tenda AC20 WifiGuestSet buffer overflow

Severity: high (CVSS 8.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.9% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2025-08-14 · updated 2026-06-17
Weakness: CWE-119

Description

A vulnerability was determined in Tenda AC20 up to 16.03.08.12. Affected is an unknown function of the file /goform/WifiGuestSet. The manipulation of the argument shareSpeed leads to buffer overflow. It is possible to launch the attack remotely. The exploit has been disclosed to the public and may be used.

Affected products

Tenda AC20: from 16.03.08.0 through 16.03.08.12

References

https://github.com/lin-3-start/lin-cve/blob/main/Tenda%20AC20/Tenda%20AC20.md
https://github.com/lin-3-start/lin-cve/blob/main/Tenda%20AC20/Tenda%20AC20.md#3-poc
https://vuldb.com/?ctiid.319902
https://vuldb.com/?id.319902
https://vuldb.com/?submit.631829
https://www.tenda.com.cn/
https://github.com/lin-3-start/lin-cve/blob/main/Tenda%20AC20/Tenda%20AC20.md

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