CVE-2026-76071 (GCVE-0-2026-76071)
Vulnerability from cvelistv5 – Published: 2026-08-24 15:42 – Updated: 2026-08-26 18:25
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)
SSVC
Exploitation: poc
Automatable: yes
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-26 18:25 UTC
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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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.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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