Buffer overflow in Tenda Ac20

CVE-2025-8940

A vulnerability was identified in Tenda AC20 up to 16.03.08.12. Affected by this vulnerability is the function strcpy of the file /goform/saveParentControlInfo. The manipulation of the argument Time leads to buffer overflow. The attack can be launched remotely. The exploit has been disclosed to the public and may be used.

Vulnerability class: Buffer Overflow

Published · last modified .

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.009 (57.1th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 57th percentile — 57.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2025-8940: held from 0.008 to 0.009.

EPSS over last 30 days · oldest: 0.008 · newest: 0.009 · change: +0.000

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2025-8940?
CVE-2025-8940 is a high-severity vulnerability in Tenda Ac20, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 8.8/10. Published 2025-08-14.
How severe is CVE-2025-8940?
High severity. CVSS v3 base score is 8.8 out of 10.
Is CVE-2025-8940 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.