No exploitation reportedFix available

CVE-2020-25767

No exploitation reported by the sources we read.

Published2021-08-18
WeaknessCWE-125

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

An issue was discovered in HCC Embedded NicheStack IPv4 4.1. The dnc_copy_in routine for parsing DNS domain names does not check whether a domain name compression pointer is pointing within the bounds of the packet (e.g., forward compression pointer jumps are allowed), which leads to an Out-of-bounds Read, and a Denial-of-Service as a consequence.

Timeline

dates in UTC

2021-08-1819:15CVE publishedNVD

Observed activity

isMalicious corpus · updated 2026-10-23 21:37 UTC

Indicators tagged with this CVE, per day0 indicators over 7 days

Block these indicators

Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2020-25767?format=txt
CSV export: https://api.ismalicious.com/edl/cve/CVE-2020-25767?format=csv
TAXII collection of exploited CVEs
The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD

Hcc-embedded nichestack ipv4

Branch	Affected	Fixed in	Source
4.1	= 4.1	no fix published	NVD

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Distribution builds and vendor advisories

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Vendor advisories

ICSA-21-217-01 CISA2 known affected
HCC Embedded InterNiche TCP/IP stack, NicheLite (Update B)
InterNiche stack: All versions prior to v4.3 · NicheLite: All versions prior to v4.3

Full record on NVD

Fix

Vendor fix CISA ICSA-21-217-01 · 2 productsHCC recommends users apply release v4.3 or later to mitigate these vulnerabilities. For more information, contact HCC.
Vendor fix CISA ICSA-21-217-01 · 2 productsAdditional vendors affected by the reported vulnerabilities have also released security advisories related to their affected products. Those advisories are as follows:

Advisories and patches

www.forescout.comMitigation

Detection

Nuclei template: none so far
Exploit-DB: no entry
Proof-of-concept repositories: none listed

Sources

NVDCVSS 3.17.5read 2026-10-23
NVDCVSS 2.05read 2026-10-23
NVDweakness (CWE)CWE-125read 2026-10-23
FIRST EPSSEPSS score1.5 %2026-10-22

Technical details

CVSS v3 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Published: 2021-08-18
Last Modified: 2026-06-17
NVD status: Modified

Frequently asked questions

What is CVE-2020-25767?

Is CVE-2020-25767 actively exploited?

Active exploitation of CVE-2020-25767 has not been confirmed. Its EPSS score was 1.5% on 2026-10-22, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2020-25767?

CVE-2020-25767 has a CVSS v3 base score of 7.5 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

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