Wavlink WL-NU516U1 260227 /cgi-bin/nas.cgi ftext Content-Length stack-based overflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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8.0$0-$5k0.97

Summaryinfo

A vulnerability classified as critical was found in Wavlink WL-NU516U1 260227. This issue affects the function ftext of the file /cgi-bin/nas.cgi. Such manipulation of the argument Content-Length leads to stack-based overflow. This vulnerability is uniquely identified as CVE-2026-4861. The attack can be launched remotely. Moreover, an exploit is present. The vendor was contacted early about this disclosure but did not respond in any way.

Detailsinfo

A vulnerability was found in Wavlink WL-NU516U1 260227 and classified as critical. Affected by this issue is the function ftext of the file /cgi-bin/nas.cgi. The manipulation of the argument Content-Length with an unknown input leads to a stack-based overflow vulnerability. Using CWE to declare the problem leads to 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). Impacted is confidentiality, integrity, and availability.

The advisory is shared for download at github.com. This vulnerability is handled as CVE-2026-4861. The exploitation is known to be easy. The attack may be launched remotely. Technical details as well as a public exploit are known.

The exploit is available 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 best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Vendor

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.8
VulDB Meta Temp Score: 8.0

VulDB Base Score: 8.8
VulDB Temp Score: 8.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Stack-based overflow
CWE: 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: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

03/25/2026 Advisory disclosed
03/25/2026 +0 days VulDB entry created
03/25/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: github.com
Status: Not defined

CVE: CVE-2026-4861 (🔒)
GCVE (CVE): GCVE-0-2026-4861
GCVE (VulDB): GCVE-100-353192
scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 03/25/2026 17:36
Changes: 03/25/2026 17:36 (57)
Complete: 🔍
Submitter: haimianbaobao
Cache ID: 216:B7B:103

Submitinfo

Accepted

  • Submit #776217: Wavlink NU516U1 V260227 Stack-based Buffer Overflow (by haimianbaobao)

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