CVE-2021-31228
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).
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (1.27%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
- EPSS
- 1.27% probability · 70th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-330
- Affected
- hcc-embedded/nichestack
- Source
- cve@mitre.org
EPSS 1.3% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://www.forescout.com/blog/new-critical-operational-technology-vulnerabilities-found-on-nichestack/Mitigation, Third Party Advisory
- 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.kb.cert.org/vuls/id/608209Third Party Advisory, US Government Resource
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.