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TI-2026-04241 Aliases CVE-2026-4861GHSA-f5jv-m3j9-f42p

Wavlink WL-NU516U1 nas.cgi ftext stack-based overflow

Priority HIGH 73CWE-119Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
No fix listed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-119 and the CVSS impact.

Summary

A weakness has been identified in Wavlink WL-NU516U1 260227. This vulnerability affects the function ftext of the file /cgi-bin/nas.cgi. This manipulation of the argument Content-Length causes stack-based buffer overflow. The attack can be initiated remotely. The exploit has been made available to the public and could be used for attacks. The vendor was contacted early about this disclosure but did not respond in any way.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00865 58th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by the CNA and NVD
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
WavlinkWL-NU516U1260227—No fix listedCNA
  • WL-NU516U1 VendorWavlink Affected 260227 Fixed in — No fix listed CNA

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:o:wavlink:wl-nu516u1_firmware:m16u1_v260227:*:*:*:*:*:*:*m16u1_v260227VulnerableWavlink
cpe:2.3:h:wavlink:wl-nu516u1:-:*:*:*:*:*:*:*not specified by NVDRunning onWavlink
  • cpe:2.3:o:wavlink:wl-nu516u1_firmware:m16u1_v260227:*:*:*:*:*:*:* Versions m16u1_v260227 Vulnerable ·Wavlink
  • cpe:2.3:h:wavlink:wl-nu516u1:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Wavlink

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-4861
  2. 2026-10-03 Alias added: GHSA-f5jv-m3j9-f42p

References

Exploit 1

  • TI-2026-03195 Wavlink NU516U1 login.cgi sub_401A10 out-of-bounds write CVSS 4.0CRITICAL 9.3
  • TI-2026-03117 Wavlink WL-NU516U1 login.cgi sub_401A0C stack-based overflow CVSS 4.0HIGH 8.6
  • TI-2026-03116 Wavlink WL-NU516U1 OTA Online Upgrade adm.cgi sub_405AF4 command injection CVSS 4.0HIGH 8.6
  • TI-2026-02231 Wavlink WL-NU516U1 firewall.cgi singlePortForwardDelete command injection CVSS 4.0HIGH 8.6
  • TI-2026-02193 Wavlink WL-NU516U1 nas.cgi sub_401218 stack-based overflow CVSS 4.0HIGH 8.6
  • TI-2026-02191 Wavlink WL-NU516U1 adm.cgi sub_40785C stack-based overflow CVSS 4.0HIGH 7.5
See all 27 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences