The DNS client in InterNiche NicheStack TCP/IP 4.0.1 is affected by: Insufficient entropy in the DNS transaction id.

published 2021-08-18 5 y ago modified 2026-06-17 4 mo ago also EUVD-2020-18556

cvss: 7.5; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 1.3%; EPSS 1.3% chance of exploitation in 30 days, percentile 69%
public exploits: 0; none known

The DNS client in InterNiche NicheStack TCP/IP 4.0.1 is affected by: Insufficient entropy in the DNS transaction id. The impact is: DNS cache poisoning (remote). The component is: dns_query_type(). The attack vector is: a specific DNS response packet.

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 2021-12-16 cvss 4.0

HCC Embedded InterNiche TCP/IP stack, NicheLite (Update B)

HCC Embedded InterNiche stack < 4.3 HCC Embedded NicheLite < 4.3
affected: 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

1.26% chance of exploitation in the next 30 days, higher than 69% 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:H/A:N
NVD	2.0	5.0	AV:N/AC:L/Au:N/C:N/I:P/A:N

Classification

Weakness

CWE-331 Insufficient Entropy

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-2020-25926
NVD CVE-2020-25926

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary