Tenda AC21 mDMZSetCfg command injection

published 2026-01-29 9 mo ago modified 2026-06-17 4 mo ago also EUVD-2026-5015

cvss: 6.3; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 2.2%; EPSS 2.2% chance of exploitation in 30 days, percentile 82%
public exploits: 0; none known

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.

CISA SSVC

Exploitation: Proof of concept is public
Automatable: no
Technical impact: partial
Assessed: 9 mo ago (2026-01-30)

Exploit prediction

2.20% chance of exploitation in the next 30 days, higher than 82% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

github.com https://github.com/LX-LX88/cve/issues/26 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	4.0	5.3	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P
CNA	3.1	6.3	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L/E:P/RL:X/RC:R
CNA	3.0	6.3	CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L/E:P/RL:X/RC:R
CNA	2.0	6.5	AV:N/AC:L/Au:S/C:P/I:P/A:P/E:POC/RL:ND/RC:UR
CNA	4.0	2.1	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CNA	3.1	6.3	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L
NVD	3.1	8.8	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CNA	2.0	6.5	AV:N/AC:L/Au:S/C:P/I:P/A:P

Affected products

Tenda AC21

Classification

Weakness

CWE-77 Improper Neutralization of Special Elements used in a Command
CWE-74 Improper Neutralization of Special Elements in Output Used by a Downstream Component

References

github.com /LX-LX88/cve/issues/26
broken-link, exploit, issue-tracking
vuldb.com /?id.343417
vdb-entry, technical-description, third-party-advisory
vuldb.com /?ctiid.343417
signature, permissions-required, vdb-entry
vuldb.com /?submit.740871
third-party-advisory, vdb-entry
tenda.com.cn /
product

Sources

CVE List CVE-2026-1638
NVD CVE-2026-1638

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary