CVE-2020-25926Network attack vector

DNS cache poisoning via predictable transaction IDs

Published Aug 18, 2021 · Updated Aug 4, 2024

Insufficient entropy in the DNS client of InterNiche NicheStack before 4.3 allows remote attackers to poison the device's DNS cache. The dns_query_type() function generates transaction IDs with too little randomness, allowing forged response packets to match outstanding DNS queries. No authentication or man-in-the-middle position is required; a successful forged reply can redirect name resolution to attacker-selected addresses.

CVSS severity7.5
High
EPSS probability1.26%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Insufficient entropy in the DNS client of InterNiche NicheStack before 4.3 allows remote attackers to poison the device's DNS cache. The dns_query_type() function generates transaction IDs with too little randomness, allowing forged response packets to match outstanding DNS queries. No authentication or man-in-the-middle position is required; a successful forged reply can redirect name resolution to attacker-selected addresses.

The record

CVE
CVE-2020-25926
Published
Aug 18, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-331, T1557
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 18, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
5.0NIST NVDAV:N/AC:L/Au:N/C:N/I:P/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-331Insufficient Entropy
T1557Adversary-in-the-Middle

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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