Buffer overflow in Tenda A21
CVE-2026-2873
A vulnerability was detected in Tenda A21 1.0.0.0. This issue affects the function setSchedWifi of the file /goform/openSchedWifi. Performing a manipulation of the argument schedStartTime/schedEndTime results in stack-based buffer overflow. It is possible to initiate the attack remotely. The exploit is now public and may be used.
Vulnerability class: Buffer Overflow
EPSS: 0.006 (43.7th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Tenda A21 — versions 1.0.0.0
- Tenda A21_firmware — versions 1.0.0.0
Weakness classification (CWE)
References
- cna@vuldb.com (technical-description, VDB Entry, Third Party Advisory, vdb-entry)
- cna@vuldb.com (signature, Permissions Required, permissions-required, VDB Entry)
- cna@vuldb.com (VDB Entry, Third Party Advisory, third-party-advisory)
- cna@vuldb.com (issue-tracking, Exploit, Third Party Advisory, exploit, Mitigation, Issue Tracking)
- cna@vuldb.com (Product, product)
Frequently asked questions
- What is CVE-2026-2873?
- CVE-2026-2873 is a high-severity vulnerability in Tenda A21, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 8.8/10. Published 2026-02-21.
- How severe is CVE-2026-2873?
- High severity. CVSS v3 base score is 8.8 out of 10.