CVE-2026-76071 (GCVE-0-2026-76071)
Vulnerability from cvelistv5 – Published: 2026-08-24 15:42 – Updated: 2026-08-24 15:42
VLAI
EPSS
VEX
Title
Netis NC63 V3.0.0.3327 Stack Buffer Overflow via destHost Parameter
Summary
Netis NC63 firmware through V3.0.0.3327 contains a stack-based buffer overflow vulnerability that allows unauthenticated remote attackers to overwrite saved stack state by supplying an oversized destHost parameter to the ipFilterList=mod action in netis.cgi. Attackers can exploit widthless sscanf conversions that copy user-supplied input into fixed-size stack buffers before authentication is verified, achieving remote code execution as root due to the Boa web server executing the CGI environment with root privileges.
Severity
9.8 (Critical)
CWE
- CWE-121 - Stack-based Buffer Overflow
Assigner
References
4 references
| URL | Tags |
|---|---|
| https://ozcanpng.dev/blog/cve-2026-76071-netis-nc… | technical-descriptionexploit |
| https://github.com/ozcanpng/CVE-2026-76071 | technical-descriptionexploit |
| https://www.netis-systems.com/products/NC63.html | product |
| https://www.vulncheck.com/advisories/netis-nc63-s… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Netis Systems | NC63 |
Affected:
0 , ≤ 3.0.0.3327
(custom)
|
guessed |
Date Public
2026-08-20 00:00
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}
}
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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