Buffer overflow in Wavlink Wl-Nu516u1-A
CVE-2026-13539
A vulnerability was identified in Wavlink WL-NU516U1-A M16U1_V240425. The impacted element is the function sub_407504 of the file /cgi-bin/wireless.cgi of the component POST Parameter Handler. Such manipulation of the argument Guest_ssid leads to stack-based buffer overflow. The attack can be executed remotely. The exploit is publicly available and might be used. It is suggested to 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 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: 0.009 · newest: 0.009 · change: 0.000
Affected products
- Wavlink Wl-Nu516u1-A — versions M16U1_V240425
Weakness classification (CWE)
References
- vuldb.com/vuln/374547 (technical-description, vdb-entry)
- vuldb.com/vuln/374547/cti (signature, permissions-required)
- vuldb.com/cve/CVE-2026-13539 (third-party-advisory)
- vuldb.com/submit/834024 (third-party-advisory)
- github.com/Svigo-o/Wavlink_vul/tree/main/wavlink-wl-nu516u1-wireless-guestwifi-… (exploit)
- dl.wavlink.com/firmware/RD/WINSTAR_NU516U1-WO-A-2026-06-22-5ccde97-mt7628-squas… (patch)
Frequently asked questions
- What is CVE-2026-13539?
- CVE-2026-13539 is a high-severity vulnerability in Wavlink Wl-Nu516u1-A, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 8.8/10. Published 2026-06-29.
- How severe is CVE-2026-13539?
- High severity. CVSS v3 base score is 8.8 out of 10.