The web server in InterNiche NicheStack through 4.0.1 allows remote attackers to cause a…
Priority LOW 38CWE-835Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-835.
Summary
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.
Why it matters now
EPSS 0.02588 85th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | — | all versions | — | No fix listed | CNA |
- — Vendor— Affected all versions Fixed in — No fix listed CNA
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:hcc-embedded:nichestack:*:*:*:*:*:*:*:* | up to 4.0.1 | Vulnerable | Hcc-embedded |
- cpe:2.3:a:hcc-embedded:nichestack:*:*:*:*:*:*:*:* Versions up to 4.0.1 Vulnerable ·Hcc-embedded
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2021-27565
- 2026-10-03 Alias added: GHSA-r4v2-qg7m-3xrh
References
More Hcc-embedded Nichestack vulnerabilities
- TI-2020-18156 An issue was discovered in HCC Nichestack 3.0. CVSS 3.1CRITICAL 9.1
- TI-2021-14884 An issue was discovered in HCC Embedded InterNiche NicheStack through 4.3. CVSS 3.1HIGH 7.5
- TI-2021-11533 An issue was discovered in tcp_rcv() in nptcp.c in HCC embedded InterNiche 4.0.1. CVSS 3.1HIGH 7.5
- TI-2020-18155 An issue was discovered in HCC Nichestack 3.0. CVSS 3.1HIGH 7.5
- TI-2020-18154 An issue was discovered in HCC Nichestack 3.0. CVSS 3.1HIGH 7.5
- TI-2021-11532 An issue was discovered in tcp_pulloutofband() in tcp_in.c in HCC embedded InterNiche… CVSS 3.1HIGH 7.5
Sources
- CVE-2021-27565 · CVE Program
- CVE-2021-27565 · NVD
- FIRST EPSS
- GHSA-r4v2-qg7m-3xrh · GitHub Advisory Database · CC BY 4.0
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