What is CVE-2026-1638?

CVE-2026-1638 is a medium-severity vulnerability in Tenda Ac21, classified under Improper Neutralization of Special Elements in Output Used by a Downstream Component (Injection). CVSS score: 6.3/10. Published 2026-01-30.

How severe is CVE-2026-1638?

Medium severity. CVSS v3 base score is 6.3 out of 10.

RCE in Tenda Ac21

CVE-2026-1638

A security flaw has been discovered in Tenda AC21 1.1.1.1/1.dmzip/16.03.08.16. The impacted element is the function mDMZSetCfg of the file /goform/mDMZSetCfg. The manipulation of the argument dmzIp results in command injection. The attack can be executed remotely. The exploit has been released to the public and may be used for attacks.

EPSS: 0.020 (79.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L.

Affected products

Tenda Ac21 — versions 1.1.1.1, 1.dmzip, 16.03.08.16
Tenda Ac21_firmware — versions 16.03.08.16

Weakness classification (CWE)

References

cna@vuldb.com (technical-description, VDB Entry, Third Party Advisory, vdb-entry)
cna@vuldb.com (signature, Permissions Required, permissions-required, VDB Entry)
cna@vuldb.com (VDB Entry, Third Party Advisory, third-party-advisory)
cna@vuldb.com (issue-tracking, exploit, broken-link, Broken Link)
cna@vuldb.com (Product, product)

Frequently asked questions

What is CVE-2026-1638?: CVE-2026-1638 is a medium-severity vulnerability in Tenda Ac21, classified under Improper Neutralization of Special Elements in Output Used by a Downstream Component (Injection). CVSS score: 6.3/10. Published 2026-01-30.
How severe is CVE-2026-1638?: Medium severity. CVSS v3 base score is 6.3 out of 10.