What is CVE-2023-39670?

CVE-2023-39670 is a critical-severity vulnerability in Tenda Ac6, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 9.8/10. Published 2023-08-18.

How severe is CVE-2023-39670?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Buffer overflow in Tenda Ac6

CVE-2023-39670

Tenda AC6 _US_AC6V1.0BR_V15.03.05.16 was discovered to contain a buffer overflow via the function fgets.

Vulnerability class: Buffer Overflow

Published 2023-08-18 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.008 (53.6th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 54th percentile — 53.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

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

Affected products

Tenda Ac6 — versions 1.0
Tenda Ac6 Firmware — versions 15.03.05.16

Weakness classification (CWE)

CWE-120 — Buffer Copy without Checking Size of Input (Classic Buffer Overflow)

References

www.tendacn.com/download/list-3.html (Product)
github.com/Davidteeri/Bug-Report/blob/main/Tenda/AC6 buffer overflow.md (Broken Link)

Frequently asked questions

What is CVE-2023-39670?: CVE-2023-39670 is a critical-severity vulnerability in Tenda Ac6, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 9.8/10. Published 2023-08-18.
How severe is CVE-2023-39670?: Critical severity. CVSS v3 base score is 9.8 out of 10.