← Vulnerability feed

Vulnerability record · CVE-2026-4565 · published 23 March 2026

CVE-2026-4565: Tenda ac21 firmware memory buffer overflow vulnerability

Tenda · Ac21 Firmware

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.

7.4 CVSS 4.0 High EPSS 0.98% · top 39.2% CWE-119 · Memory buffer overflowCWE-120 · Classic buffer overflow
7.4CVSS 4.0 base score, v2 9.0
0.98%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
6References, 2 tagged exploit
17 Jun 2026Last modified by NVD

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:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/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:

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://github.com/hellonestor/killallbug/issues/14 ExploitIssue Tracking
https://github.com/hellonestor/killallbug/releases/tag/poc Exploit
https://vuldb.com/?ctiid.352402 Permissions RequiredVDB Entry
https://vuldb.com/?id.352402 Third Party AdvisoryVDB Entry
https://vuldb.com/?submit.775119 Third Party AdvisoryVDB Entry
https://www.tenda.com.cn/ Product

Track CVE-2026-4565 inside VULONE

Watch it alongside the ransomware crews, C2 infrastructure and forum chatter that reference it, query it through the API and pull it into your SIEM over TAXII.

Start free Open in platform

Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

8.9CVE-2025-9605Tenda ac21 firmware memory buffer overflow vulnerabilityA security vulnerability has been detected in Tenda AC21 and AC23 16.03.08.16. Affected is the function GetParentControlInfo of the file /goform/GetP…EPSS 5.1%8.8CVE-2023-24333Tenda ac21 firmware code injection vulnerabilityA stack overflow vulnerability in Tenda AC21 with firmware version US_AC21V1.0re_V16.03.08.15_cn_TDC01 allows attackers to run arbitrary commands via…EPSS 0.48%7.5CVE-2022-44158Tenda ac21 firmware out-of-bounds write vulnerabilityTenda AC21 V16.03.08.15 is vulnerable to Buffer Overflow via function via set_device_name.EPSS 0.85%7.5CVE-2022-44163Tenda ac21 firmware out-of-bounds write vulnerabilityTenda AC21 V16.03.08.15 is vulnerable to Buffer Overflow via function formSetMacFilterCfg.EPSS 0.85%7.5CVE-2022-40067Tenda ac21 firmware out-of-bounds write vulnerabilityTenda AC21 V 16.03.08.15 is vulnerable to Buffer Overflow via /bin/httpd, function: formSetVirtualSer.EPSS 0.99%7.5CVE-2022-40068Tenda ac21 firmware out-of-bounds write vulnerabilityTenda AC21 V16.03.08.15 is vulnerable to Buffer Overflow via /bin/httpd, function: formSetQosBand.EPSS 0.99%7.5CVE-2022-40069Tenda ac21 firmware out-of-bounds write vulnerability]Tenda AC21 V 16.03.08.15 is vulnerable to Buffer Overflow via /bin/httpd, function: fromSetSysTime.EPSS 0.99%7.5CVE-2022-40070Tenda ac21 firmware out-of-bounds write vulnerabilityTenda AC21 V 16.03.08.15 is vulnerable to Buffer Overflow via bin/httpd, function: formSetFirewallCfg.EPSS 0.99%

Source: NIST National Vulnerability Database (record CVE-2026-4565), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.