Buffer overflow in Totolink A800r
CVE-2026-19811
A security flaw has been discovered in TOTOLINK A800R 4.1.2cu.5137_B20200730. The impacted element is the function setIpQosRules of the file /cgi-bin/cstecgi.cgi of the component firewall.so. The manipulation of the argument Comment 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.
Vulnerability class: Buffer Overflow
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
- Totolink A800r — versions 4.1.2cu.5137_B20200730
Weakness classification (CWE)
References
- cna@vuldb.com (technical-description, vdb-entry)
- cna@vuldb.com (signature, permissions-required)
- cna@vuldb.com (third-party-advisory)
- cna@vuldb.com (third-party-advisory)
- cna@vuldb.com (exploit)
- cna@vuldb.com (product)
Frequently asked questions
- What is CVE-2026-19811?
- CVE-2026-19811 is a high-severity vulnerability in Totolink A800r, 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-2026-19811?
- High severity. CVSS v3 base score is 8.8 out of 10.