CVE-2020-17439

HIGH
8.3
CVSS Score
Published: December 11, 2020 at 10:26 PM UTC
Updated: June 17, 2026 at 02:58 AM UTC
1 product affected across 1 vendorUip· also runs on 1 platform

Using N/A by N/A?

Get instant alerts when new vulnerabilities affect N/A - before attackers find them.

Real-time alertsTrack your software stackFree plan available
Severity
HIGH8.3
Exploit prediction
EPSS 3%

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

contiki-os-contiki (environment)

Runs on — not affected

The affected product only carries this flaw when running on these platforms. The platforms themselves are not vulnerable.

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

References (2)

x_refsource_MISCThird Party AdvisoryUS Government Resource
https://us-cert.cisa.gov/ics/advisories/icsa-20-343-01
x_refsource_MISCThird Party AdvisoryUS Government Resource
https://www.kb.cert.org/vuls/id/815128

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
CHANGED
Confidentiality
LOW
Integrity
LOW
Availability
LOW
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-20

Get alerted

Stop reading CVE feeds looking for your own stack

Track the products you run and VulnTracker tells you when a new CVE affects them — with what is known about fixing it, and nothing about the rest.

Free plan, no card