CVE-2021-27565

The web server in InterNiche NicheStack through 4.0.1 allows remote attackers to cause a denial of service (infinite loop and networking outage) via an unexpected valid HTTP request such as OPTIONS. This occurs because the HTTP request handler enters a miscoded wbs_loop() debugger hook.

• CWE-835

• https://www.forescout.com/blog/new-critical-operational-technology-vulnerabilities-found-on-nichestack/Mitigation, Third Party Advisory
• https://www.hcc-embedded.com/Product
• https://www.hcc-embedded.com/about/about-internicheProduct
• https://www.kb.cert.org/vuls/id/608209Third Party Advisory, US Government Resource
• https://www.forescout.com/blog/new-critical-operational-technology-vulnerabilities-found-on-nichestack/Mitigation, Third Party Advisory
• https://www.hcc-embedded.com/Product
• https://www.hcc-embedded.com/about/about-internicheProduct
• https://www.kb.cert.org/vuls/id/608209Third Party Advisory, US Government Resource

Published

Aug 19, 2021

Last Modified

Jun 17, 2026

Status

Modified

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