Critical severity · published Mar 8, 2026
CVE-2026-3703
Wavlink NU516U1 login.cgi sub_401A10 out-of-bounds write
9.8
CVSS
0.8%
EPSS
No
On KEV
Description
A flaw has been found in Wavlink NU516U1 251208. This affects the function sub_401A10 of the file /cgi-bin/login.cgi. Executing a manipulation of the argument ipaddr can lead to out-of-bounds write. The attack may be performed from remote. The exploit has been published and may be used. Upgrading the affected component is recommended. 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)0.8% · higher than 58% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
NU
NU516U1 · Wavlink
251208 · source: vendor
WF
Wl-nu516u1 Firmware · Wavlink
251208 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-3703
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-3703
Broken Link
https://dl.wavlink.com/firmware/RD/WINSTAR_NU516U1-WO-A-2026-02-27-2fcf6ae-mt7628-squashfs-sysupgrade.bin
Exploit
https://github.com/Wlz1112/Wavlink-NU516U1-V251208-/blob/main/ipaddr.md
Exploit
https://github.com/Wlz1112/Wavlink-NU516U1-V251208-/blob/main/ipaddr.md#exp-exploit--poc
Permissions Required
https://vuldb.com/?ctiid.349649
Third Party Advisory
https://vuldb.com/?id.349649
Third Party Advisory
https://vuldb.com/?submit.759226
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