Wavlink WL-NU516U1 up to 130/260 /cgi-bin/adm.cgi sub_406194 firmware_url stack-based overflow
Summary
A vulnerability identified as critical has been detected in Wavlink WL-NU516U1 up to 130/260. This vulnerability affects the function sub_406194 of the file /cgi-bin/adm.cgi. Performing a manipulation of the argument firmware_url results in stack-based overflow.
This vulnerability was named CVE-2026-2566. The attack may be initiated remotely. In addition, an exploit is available.
The vendor was contacted early about this disclosure but did not respond in any way.
Details
A vulnerability was found in Wavlink WL-NU516U1 up to 130/260. It has been classified as critical. This affects the function sub_406194 of the file /cgi-bin/adm.cgi. The manipulation of the argument firmware_url with an unknown input leads to a stack-based overflow vulnerability. CWE is classifying the issue as CWE-121. A stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function). This is going to have an impact on confidentiality, integrity, and availability.
The advisory is shared at github.com. This vulnerability is uniquely identified as CVE-2026-2566. The exploitability is told to be easy. It is possible to initiate the attack remotely. Additional levels of successful authentication are necessary for exploitation. Technical details and a public exploit are known.
The exploit is shared for download at github.com. It is declared as proof-of-concept. The vendor was contacted early about this disclosure but did not respond in any way.
There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Product
Vendor
Name
Version
License
CPE 2.3
CPE 2.2
CVSSv4
VulDB Vector: 🔒VulDB Reliability: 🔍
CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒
CVSSv3
VulDB Meta Base Score: 7.2VulDB Meta Temp Score: 6.8
VulDB Base Score: 7.2
VulDB Temp Score: 6.5
VulDB Vector: 🔒
VulDB Reliability: 🔍
CNA Base Score: 7.2
CNA Vector: 🔒
CVSSv2
| AV | AC | Au | C | I | A |
|---|---|---|---|---|---|
| 💳 | 💳 | 💳 | 💳 | 💳 | 💳 |
| 💳 | 💳 | 💳 | 💳 | 💳 | 💳 |
| 💳 | 💳 | 💳 | 💳 | 💳 | 💳 |
| Vector | Complexity | Authentication | Confidentiality | Integrity | Availability |
|---|---|---|---|---|---|
| Unlock | Unlock | Unlock | Unlock | Unlock | Unlock |
| Unlock | Unlock | Unlock | Unlock | Unlock | Unlock |
| Unlock | Unlock | Unlock | Unlock | Unlock | Unlock |
VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍
Exploiting
Class: Stack-based overflowCWE: CWE-121 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒
Physical: No
Local: No
Remote: Yes
Availability: 🔒
Access: Public
Status: Proof-of-Concept
Download: 🔒
EPSS Score: 🔒
EPSS Percentile: 🔒
Price Prediction: 🔍
Current Price Estimation: 🔒
| 0-Day | Unlock | Unlock | Unlock | Unlock |
|---|---|---|---|---|
| Today | Unlock | Unlock | Unlock | Unlock |
Threat Intelligence
Interest: 🔍Active Actors: 🔍
Active APT Groups: 🔍
Countermeasures
Recommended: no mitigation knownStatus: 🔍
0-Day Time: 🔒
Timeline
02/15/2026 Advisory disclosed02/15/2026 VulDB entry created
02/20/2026 VulDB entry last update
Sources
Advisory: github.comStatus: Not defined
CVE: CVE-2026-2566 (🔒)
GCVE (CVE): GCVE-0-2026-2566
GCVE (VulDB): GCVE-100-346173
scip Labs: https://www.scip.ch/en/?labs.20161013
Entry
Created: 02/15/2026 20:45Updated: 02/20/2026 10:46
Changes: 02/15/2026 20:45 (57), 02/16/2026 21:43 (31), 02/20/2026 10:46 (1)
Complete: 🔍
Submitter: haimianbaobao
Cache ID: 216::103
Submit
Accepted
- Submit #751908: Wavlink NU516U1 V251208 Stack-based Buffer Overflow (by haimianbaobao)
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
No comments yet. Languages: en.
Please log in to comment.