Vulnerability · Published Feb 21, 2026 · Assigned by VulDB
CVE-2026-2870Tenda A21 formSetQosBand set_qosMib_list stack-based overflow
High 8.8
In plain English
A high-severity stack buffer overflow in A21 from Tenda. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.7% (higher than 52% of all known vulnerabilities).
Severity (CVSS 3.1)8.8High
Exploit odds (30 days)0.7%top 47.9% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known
Official 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.
Affected products (as reported)
Weakness: CWE-121, CWE-119 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:P/RL:X/RC:R
References
- VDB-347107 | Tenda A21 formSetQosBand set_qosMib_list stack-based overflow vdb-entry, technical-description
- VDB-347107 | CTI Indicators (IOB, IOC, IOA) signature, permissions-required
- Submit #754627 | Tenda A21 V1.0.0.1 Stack-based Buffer Overflow third-party-advisory
- https://github.com/QIU-DIE/cve-nneeww/issues/1 exploit, issue-tracking
- https://www.tenda.com.cn/ product