CVE-2020-17439

Description

An issue was discovered in uIP 1.0, as used in Contiki 3.0 and other products. The code that parses incoming DNS packets does not validate that the incoming DNS replies match outgoing DNS queries in newdata() in resolv.c. Also, arbitrary DNS replies are parsed if there was any outgoing DNS query with a transaction ID that matches the transaction ID of an incoming reply. Provided that the default DNS cache is quite small (only four records) and that the transaction ID has a very limited set of values that is quite easy to guess, this can lead to DNS cache poisoning.

Category

8.3
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.38%
Third-Party Advisory cisa.gov Third-Party Advisory cert.org
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://www.kb.cert.org/vuls/id/815128 third party advisory us government resource
https://us-cert.cisa.gov/ics/advisories/icsa-20-343-01 third party advisory us government resource

Frequently Asked Questions

What is the severity of CVE-2020-17439?
CVE-2020-17439 has been scored as a high severity vulnerability.
How to fix CVE-2020-17439?
To fix CVE-2020-17439, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2020-17439 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2020-17439 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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