High severity · published Mar 23, 2026
CVE-2026-4565
Tenda AC21 SetNetControlList formSetQosBand buffer overflow
8.8
CVSS
1%
EPSS
No
On KEV
Description
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.
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)1.0% · higher than 61% 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-2026-4565
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-4565
Exploit
https://github.com/hellonestor/killallbug/issues/14
Exploit
https://github.com/hellonestor/killallbug/releases/tag/poc
Permissions Required
https://vuldb.com/?ctiid.352402
Third Party Advisory
https://vuldb.com/?id.352402
Third Party Advisory
https://vuldb.com/?submit.775119
Product
https://www.tenda.com.cn/
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