Buffer overflow in Tenda Ac21

CVE-2025-11091

A security flaw has been discovered in Tenda AC21 up to 16.03.08.16. Affected by this vulnerability is the function sscanf of the file /goform/SetStaticRouteCfg. The manipulation of the argument list results in buffer overflow. The attack can be launched remotely. The exploit has been released to the public and may be exploited.

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: 0.007 (52.6th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 53rd percentile — 52.6% 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-2025-11091: held from 0.007 to 0.007.

EPSS over last 30 days · oldest: 0.007 · newest: 0.007 · change: 0.000

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2025-11091?
CVE-2025-11091 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 2025-09-28.
How severe is CVE-2025-11091?
High severity. CVSS v3 base score is 8.8 out of 10.
Is CVE-2025-11091 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.