Buffer overflow in Totolink A800r
CVE-2026-19813
A security vulnerability has been detected in TOTOLINK A800R 4.1.2cu.5137_B20200730. This impacts the function setMacFilterRules of the file /cgi-bin/cstecgi.cgi of the component firewall.so. Such manipulation of the argument Comment leads to stack-based buffer overflow. The attack may be performed from remote. The exploit has been disclosed publicly and may be used.
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 (56.7th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 57th percentile — 56.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.006 · newest: 0.009 · change: +0.003
Affected products
- Totolink A800r — versions 4.1.2cu.5137_B20200730
Weakness classification (CWE)
References
- github.com/panda666-888/vuls/blob/main/totolink/a800r/setMacFilterRules.md (exploit)
- vuldb.com/cve/CVE-2026-19813 (third-party-advisory)
- vuldb.com/submit/869430 (third-party-advisory)
- vuldb.com/vuln/389949 (technical-description, vdb-entry)
- vuldb.com/vuln/389949/cti (signature, permissions-required)
- www.totolink.net/ (product)
Frequently asked questions
- What is CVE-2026-19813?
- CVE-2026-19813 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-2026-19813?
- High severity. CVSS v3 base score is 8.8 out of 10.