CVE-2026-18588: Wavlink WL-NU516U1 · Stack-based Buffer Overflow
Affects Wavlink WL-NU516U1Source CVE Database V5
Public exploit available · CVSS 9.3 Critical.
Data as of 26 Oct 2026, 10:12 UTC
- EPSS
- 1.0% chance of exploitation in 30 days – higher than 65% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- CISA SSVC
- Exploitation
- Proof of concept is public or traded
- Automatable
- Attackers can reliably automate steps 1–4 of the kill chain
- Technical impact
- Total control over the software or total information disclosure
CISA SSVC assessment, 2026-08-03.
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:XExploitation evidence
t = 0 is the CVE’s publication on cve.org
Disclosed: evidence found.
CVE published 3 Aug 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: evidence found.
CISA SSVC: proof of concept public
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
Timeline
CVE ID reserved
by VulDB
, 9 hours before disclosure
CVE published
on cve.org
, t = 0
CISA SSVC assessment
proof of concept public
, 9 hours after disclosure
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), CISA SSVC, the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| WavlinkWL-NU516U1 | Affected
| Fixed in– |
Description
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.
References
- vuldb.com/vuln/385416 (opens in a new tab)
- vuldb.com/vuln/385416/cti (opens in a new tab)
- vuldb.com/cve/CVE-2026-18588 (opens in a new tab)
- vuldb.com/submit/850500 (opens in a new tab)
- github.com/oduoke567/WAVLINK-NU516U1-2026-05-1/blob/main/report2.md (opens in a new tab)
- dl.wavlink.com/firmware/RD/WINSTAR_NU516U1-WO-A-2026-07-13-4b8a21f-mt7628-squashfs-sysupgrade.bin (opens in a new tab)