CVE-2026-2870 Details
Description
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.
A stack-based buffer overflow vulnerability has been identified in the Tenda A21 router, specifically in the firmware version 1.0.0.0. The issue arises in the QoS configuration endpoint '/goform/formSetQosBand', within the 'set_qosMib_list' function. This function processes a user-controlled 'list' parameter without proper input validation, using the unsafe 'strcpy' function to copy data into a fixed-size stack buffer of 256 bytes. This lack of bounds checking allows for overwriting the stack frame, which could lead to arbitrary code execution or a denial-of-service condition by crashing the HTTP service.
Users are advised to update to a version of the Tenda A21 router firmware that addresses this vulnerability. As of now, no specific patch has been mentioned, but users should check the Tenda official website or contact Tenda support for guidance on updating their firmware.
Metrics
CVSS 4.0 Severity and Vector Strings:
CVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
CISA-ADP
Assessed Feb 23, 2026References to Advisories, Solutions, and Tools
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| URL | Source(s) | Tag(s) |
|---|---|---|
| https://github.com/QIU-DIE/cve-nneeww/issues/1 | [email protected] | ExploitIssue TrackingMitigationThird Party Advisory |
| https://vuldb.com/?ctiid.347107 | [email protected] | Permissions RequiredVDB Entry |
| https://vuldb.com/?id.347107 | [email protected] | Third Party AdvisoryVDB Entry |
| https://vuldb.com/?submit.754627 | [email protected] | Third Party AdvisoryVDB Entry |
| https://www.tenda.com.cn/ | [email protected] | Product |
Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| CWE-119 | Improper Restriction of Operations within the Bounds of a Memory Buffer | [email protected] |
| CWE-121 | Stack-based Buffer Overflow | [email protected] |
Affected Products
| Product | Versions |
|---|---|
| tenda a21 firmware | 1.0.0.0 |
CPE
Remediation
| |
| tenda a21 | All versions |
CPE
Remediation
| |
Change History
4 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Jun 17, 2026 | CVE Modified | [email protected] |
| Jun 17, 2026 | CVE Modified | CISA-ADP |
| Feb 23, 2026 | Initial Analysis | [email protected] |
| Feb 21, 2026 | New CVE Received | [email protected] |