High severity · published Jan 29, 2026
CVE-2026-1637
Tenda AC21 AdvSetMacMtuWan fromAdvSetMacMtuWan stack-based overflow
8.8
CVSS
0.7%
EPSS
No
On KEV
Description
A vulnerability was identified in Tenda AC21 16.03.08.16. The affected element is the function fromAdvSetMacMtuWan of the file /goform/AdvSetMacMtuWan. The manipulation leads to stack-based buffer overflow. Remote exploitation of the attack is possible. The exploit is publicly available and might be used.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.7% · higher than 53% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AC
AC21 · Tenda
16.03.08.16 · source: vendor
AF
Ac21 Firmware · Tenda
16.03.08.16 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-1637
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-1637
Broken Link
https://github.com/LX-LX88/cve/issues/25
Permissions Required
https://vuldb.com/?ctiid.343416
Third Party Advisory
https://vuldb.com/?id.343416
Third Party Advisory
https://vuldb.com/?submit.740865
Product
https://www.tenda.com.cn/
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