What’s Vulnerable › Vulnerabilities

CVE-2021-31228

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.3% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2021-08-19 · updated 2026-06-17
• Weakness: CWE-330

Description

An issue was discovered in HCC embedded InterNiche 4.0.1. This vulnerability allows the attacker to predict a DNS query's source port in order to send forged DNS response packets that will be accepted as valid answers to the DNS client's requests (without sniffing the specific request). Data is predictable because it is based on the time of day, and has too few bits.

Affected products

• Hcc-Embedded Nichestack: before 4.3 — fixed in 4.3

How to fix

Upgrade to a fixed version: Hcc-Embedded Nichestack 4.3. Check the vendor advisory for mitigations.

References

• https://www.forescout.com/blog/new-critical-operational-technology-vulnerabilities-found-on-nichestack/
• https://www.kb.cert.org/vuls/id/608209
• https://www.forescout.com/blog/new-critical-operational-technology-vulnerabilities-found-on-nichestack/
• https://www.kb.cert.org/vuls/id/608209

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