Buffer overflow in Wavlink Wl-Nu516u1
CVE-2026-18588
A vulnerability has been found in Wavlink WL-NU516U1 708c073-mt7628. This affects the function fgets of the file nas.cgi. The manipulation of the argument CONTENT_LENGTH leads to stack-based buffer overflow. Remote exploitation of the attack is possible. You should upgrade the affected component. The vendor was contacted early, responded in a very professional manner and quickly released a fixed version of the affected product.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.011 (65.6th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 66th percentile — 65.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.011 · newest: 0.011 · change: 0.000
Affected products
- Wavlink Wl-Nu516u1 — versions 708c073-mt7628
Weakness classification (CWE)
References
- vuldb.com/vuln/385416 (technical-description, vdb-entry)
- vuldb.com/vuln/385416/cti (signature, permissions-required)
- vuldb.com/cve/CVE-2026-18588 (third-party-advisory)
- vuldb.com/submit/850500 (third-party-advisory)
- github.com/oduoke567/WAVLINK-NU516U1-2026-05-1/blob/main/report2.md (broken-link)
- dl.wavlink.com/firmware/RD/WINSTAR_NU516U1-WO-A-2026-07-13-4b8a21f-mt7628-squas… (patch, broken-link)
Frequently asked questions
- What is CVE-2026-18588?
- CVE-2026-18588 is a critical-severity vulnerability in Wavlink Wl-Nu516u1, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 9.8/10. Published 2026-08-03.
- How severe is CVE-2026-18588?
- Critical severity. CVSS v3 base score is 9.8 out of 10.