CVE-2026-4565

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 v3 8.8 HIGH
CVSS v2.0 9.0 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

9.0^/10

CVSS v2.0 : HIGH

Vector : AV:N/AC:L/Au:S/C:C/I:C/A:C

Exploitability : 8.0 / Impact : 10.0

Access Vector NETWORK

Access Complexity LOW

Authentication SINGLE

Confidentiality Impact COMPLETE

Integrity Impact COMPLETE

Availability Impact COMPLETE

References

Link	Resource
https://github.com/hellonestor/killallbug/issues/14	Exploit Issue Tracking
https://github.com/hellonestor/killallbug/releases/tag/poc	Exploit
https://vuldb.com/?ctiid.352402	Permissions Required VDB Entry
https://vuldb.com/?id.352402	Third Party Advisory VDB Entry
https://vuldb.com/?submit.775119	Third Party Advisory VDB Entry
https://www.tenda.com.cn/	Product

Configurations

Configuration 1 (hide)

AND

cpe:2.3:o:tenda:ac21_firmware:16.03.08.16:*:*:*:*:*:*:*

cpe:2.3:h:tenda:ac21:1.0:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-03-23 01:16

Updated : 2026-06-17 10:56

NVD link : CVE-2026-4565

Mitre link : CVE-2026-4565

CVE.ORG link : CVE-2026-4565

JSON object : View

Products Affected

tenda

ac21_firmware
ac21

CWE

CWE-119

Improper Restriction of Operations within the Bounds of a Memory Buffer

CWE-120

Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')

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