Critical severity · published Aug 3, 2026
CVE-2026-18588
Wavlink WL-NU516U1 nas.cgi fgets stack-based overflow
9.8
CVSS
1.1%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.1% · higher than 65% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
WL
WL-NU516U1 · Wavlink
708c073-mt7628 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-18588
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-18588
dl.wavlink.com
https://dl.wavlink.com/firmware/RD/WINSTAR_NU516U1-WO-A-2026-07-13-4b8a21f-mt7628-squashfs-sysupgrade.bin
github.com
https://github.com/oduoke567/WAVLINK-NU516U1-2026-05-1/blob/main/report2.md
vuldb.com
https://vuldb.com/cve/CVE-2026-18588
vuldb.com
https://vuldb.com/submit/850500
vuldb.com
https://vuldb.com/vuln/385416
vuldb.com
https://vuldb.com/vuln/385416/cti
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