HOMEVULNERABILITIESCVE-2020-17440
HIGH

CVE-2020-17440

NVD-CWE-OtherPublished: December 11, 2020· Updated: Jun 17, 2026

7.5
CVSS v3.1

Official 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 domain names present in the DNS responses have '\0' termination. This results in errors when calculating the offset of the pointer that jumps over domain name bytes in DNS response packets when a name lacks this termination, and eventually leads to dereferencing the pointer at an invalid/arbitrary address, within newdata() and parse_name() in resolv.c.

NVD Source

Technical Analysis

CVE-2020-17440 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.

A successful exploit results in availability disruption (denial of service), with a CVSS base score of 7.5.

CVSS v3.1 Vector Breakdown

Exploitability
Attack VectorNetwork
Attack ComplexityLow
Privileges Req.None
User InteractionNone
ScopeUnchanged
Impact
ConfidentialityNone
IntegrityNone
AvailabilityHigh
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected Vendors & Products

contiki-os1 product(s)
contiki
uip_project1 product(s)
uip
Source: NVD CPE · 2 total CPE entries

Exploit & PoC Resources

NO KNOWN EXPLOITNo public exploit confirmed at this time
External links open in a new tab. Always verify in a controlled environment before use.

Official Patches & Advisories

All References (4)

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
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

Quick Facts

CVE IDCVE-2020-17440
CVSS Score7.5 / 10
SeverityHIGH
CISA KEVNo
Affected2 vendor(s)
PublishedDec 11, 2020

Related CVEs (NVD-CWE-Other)

Recommended Actions

  • Apply vendor patches immediately
  • Monitor CVE-2020-17440 in threat intel feeds
  • Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWATCH.COM. CVE data is provided under the NVD usage policy.