Skip to content
CVE Tracker
  • Newest CVEsPage
  • Recently added to KEVPage
  • Rising exploitation (EPSS)Page
  • Weekly digestPage
  • StatisticsPage
  • WatchlistPage
  • API documentationPage
  • MCP serverPage
  • Data sourcesPage
  • ChangelogPage
  • AboutPage
  • How it's builtPage
Back

CVE-2020-17439

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…

High8.3EPSS 3.2%
Published
Updated
Reserved
Assigned by
mitre

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.

Scores

CVSS scores of CVE-2020-17439, by who scored it
Scored byCVSSScoreVector
NVDNVD · Modified3.1High8.3CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:L
EPSS (exploitation in 30 days)
3.2% · top 12% of all CVEs (6 Nov 2026)
Loading the EPSS history…

The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.3.

Weakness

Affected products

  • n/a

    • affected n/a

References (2)

Sources

The same CVE in the primary databases and aggregators, to check against.

Badge for a README or a ticket

CVE-2020-17439 badge
[![CVE-2020-17439](https://trackcve.app/badge/CVE-2020-17439.svg)](https://trackcve.app/cve/CVE-2020-17439)

Record last updated .