Buffer overflow in Tenda Ac12
CVE-2026-19821
A vulnerability was determined in Tenda AC12 15.03.06.23_multi_TD01. This vulnerability affects the function formSetRebootTimer of the file /goform/SetSysAutoRebbotCfg of the component httpd web management interface. This manipulation of the argument rebootTime causes buffer overflow. The attack may be initiated remotely. The exploit has been publicly disclosed and may be utilized.
Vulnerability class: Buffer Overflow
Published · last modified .
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.
EPSS exploit prediction
EPSS: 0.009 (56.6th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 57th percentile — 56.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.005 · newest: 0.009 · change: +0.004
Affected products
- Tenda Ac12 — versions 15.03.06.23_multi_TD01
Weakness classification (CWE)
References
- github.com/lipenghai/iot_bug/blob/main/Tenda/AC12/4.md (exploit)
- vuldb.com/cve/CVE-2026-19821 (third-party-advisory)
- vuldb.com/submit/868922 (third-party-advisory)
- vuldb.com/vuln/389954 (technical-description, vdb-entry)
- vuldb.com/vuln/389954/cti (signature, permissions-required)
- www.tenda.com.cn/ (product)
Frequently asked questions
- What is CVE-2026-19821?
- CVE-2026-19821 is a high-severity vulnerability in Tenda Ac12, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 8.8/10. Published 2026-08-14.
- How severe is CVE-2026-19821?
- High severity. CVSS v3 base score is 8.8 out of 10.