A21 Firmware CVE-2026-2870
HIGHCVSS VectorNVD
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Lifecycle Timeline
3DescriptionNVD
A security flaw has been discovered in Tenda A21 1.0.0.0. Affected by this issue is the function set_qosMib_list of the file /goform/formSetQosBand. The manipulation of the argument list results in stack-based buffer overflow. The attack can be executed remotely. The exploit has been released to the public and may be used for attacks.
AnalysisAI
Remote code execution in Tenda A21 firmware through a stack buffer overflow in the QoS bandwidth configuration endpoint allows unauthenticated attackers to execute arbitrary code with full system privileges. Public exploit code exists for this vulnerability, and no patch is currently available. …
Sign in for full analysis, threat intelligence, and remediation guidance.
RemediationAI
Within 24 hours: Inventory all Tenda A21 1.0.0.0 devices in your environment and restrict administrative access to the /goform/formSetQosBand endpoint. Within 7 days: Implement network segmentation to isolate affected routers and disable QoS management features if operationally feasible, or restrict access via firewall rules. …
Sign in for detailed remediation steps.
Share
External POC / Exploit Code
Leaving vuln.today