CVE-2020-24334

The code that processes DNS responses in uIP through 1.0, as used in Contiki and Contiki-NG, does not check whether the number of responses specified in the DNS packet header corresponds to the response data available in the DNS packet, leading to an out-of-bounds read and Denial-of-Service in resolv.c.

Published: 2020-12-11 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2020-24334 is rated Moderate Risk (57.4/100): CVSS High severity, with medium exploitation likelihood (EPSS 0.64%). Mandatory action: Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2020-24334

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2025-12-13 0.50% 0.64% +0.14%
2 2025-03-30 0.35% 0.50% +0.15%
3 2025-03-29 0.35%

Full EPSS history (9 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2020-24334

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.2 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
3.9 4.2 [email protected]
6.4 2.0 MEDIUM
AV:N/AC:L/Au:N/C:N/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
10.0 4.9 [email protected]

Weakness enumeration for CVE-2020-24334

Affected software / configurations for CVE-2020-24334

Vendor Product Version Raw CPE
uip_project uip <= 1.0 cpe:2.3:a:uip_project:uip:*:*:*:*:*:*:*:*

References for CVE-2020-24334

URL Tags
https://us-cert.cisa.gov/ics/advisories/icsa-20-343-01 Third Party Advisory US Government Resource
https://www.kb.cert.org/vuls/id/815128 Third Party Advisory US Government Resource
cvelogic Threat Intelligence