CVE-2021-31227 json
An issue was discovered in HCC embedded InterNiche 4.0.1.
published 2021-08-19 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-18140
- cvss
- 7.5
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.7%
- EPSS 1.7% chance of exploitation in 30 days, percentile 77%
- public exploits
- 0
- none known
Summary
An issue was discovered in HCC embedded InterNiche 4.0.1. A potential heap buffer overflow exists in the code that parses the HTTP POST request, due to an incorrect signed integer comparison. This vulnerability requires the attacker to send a malformed HTTP packet with a negative Content-Length, which bypasses the size checks and results in a large heap overflow in the wbs_multidata buffer copy.
Patch / fix
- hcc-embedded nichestack 4.3
Vendor advisories
What the vendors themselves say about their products: affected, fixed or not affected, and what to do.
cisa ICSA-21-217-01 updated cvss 7.5
HCC Embedded InterNiche TCP/IP stack, NicheLite (Update B)
-
HCC Embedded InterNiche stack < 4.3 HCC Embedded NicheLite < 4.3affected: vendor fix mitsubishielectric.com
From CISA ICS and IT advisories (CSAF, https://github.com/cisagov/CSAF), a U.S. Government work; changed: reduced to products, statuses and remediations. CISA notification · csaf
Exploit prediction
1.68% chance of exploitation in the next 30 days, higher than 77% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| NVD | 2.0 | 5.0 | AV:N/AC:L/Au:N/C:N/I:N/A:P |
Classification
- Weakness
-
- CWE-787 Out-of-bounds Write
References
-
forescout.com
/blog/new-critical-operational-technology-vulnerabilities-found-on-nichestack/
mitigation, third-party-advisory
-
kb.cert.org
/vuls/id/608209
third-party-advisory, us-government-resource
Sources
- CVE List CVE-2021-31227
- NVD CVE-2021-31227
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