Buffer overflow in Tenda Ac21

CVE-2026-4565

A vulnerability was detected in Tenda AC21 16.03.08.16. Impacted is the function formSetQosBand of the file /goform/SetNetControlList. Performing a manipulation of the argument list results in buffer overflow. The attack can be initiated remotely. The exploit is now public and may be used.

Vulnerability class: Buffer Overflow

EPSS: 0.009 (57.2th percentile) — read the EPSS interpretation.

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.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-4565?
CVE-2026-4565 is a high-severity vulnerability in Tenda Ac21, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 8.8/10. Published 2026-03-23.
How severe is CVE-2026-4565?
High severity. CVSS v3 base score is 8.8 out of 10.