CVE-2020-17470

Name: CVE-2020-17470
Creator: NVD / NIST
Published: 2020-12-11T23:15:13.747+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.3/10EPSS 2.07%

Last modified Jun 17, 2026

CVE-2020-17470 is a medium-severity vulnerability rated 5.3/10 on the CVSS scale. An issue was discovered in FNET through 4.6.4. The code that initializes the DNS client interface structure does not set sufficiently random transaction IDs (they are always set to 1 in _fnet_dns_poll in fnet_dns.c). EPSS estimates a 2.07% chance of exploitation in the next 30 days.

Description

An issue was discovered in FNET through 4.6.4. The code that initializes the DNS client interface structure does not set sufficiently random transaction IDs (they are always set to 1 in _fnet_dns_poll in fnet_dns.c). This significantly simplifies DNS cache poisoning attacks.

Metrics

CVSS 3.1

5.3/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

EPSS Probability

2.07%

79.0th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-330

Affected Software

Vendor	Product	Versions
Butok	Fnet	<= 4.6.4

References

http://fnet.sourceforge.net/manual/fnet_history.htmlRelease Notes, Third Party Advisory
https://us-cert.cisa.gov/ics/advisories/icsa-20-343-01Third Party Advisory, US Government Resource
https://www.kb.cert.org/vuls/id/815128Third Party Advisory, US Government Resource
http://fnet.sourceforge.net/manual/fnet_history.htmlRelease Notes, Third Party Advisory
https://us-cert.cisa.gov/ics/advisories/icsa-20-343-01Third Party Advisory, US Government Resource
https://www.kb.cert.org/vuls/id/815128Third Party Advisory, US Government Resource

Timeline

Published: Dec 11, 2020
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-17470?

How severe is CVE-2020-17470?

CVE-2020-17470 has a CVSS score of 5.3/10 (MEDIUM severity). The EPSS model estimates a 2.07% probability of exploitation in the next 30 days.

How do I fix CVE-2020-17470?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2020-17470?

Run a free Strix scan to check your systems for this vulnerability.

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Source: NVD / NIST