How severe is CVE-2020-13986?

CVE-2020-13986 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2020-13986 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-13986?

CVE-2020-13986 affects Contiki-os Contiki. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-13986?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2020-13986 published?

CVE-2020-13986 was published on 2020-12-11 and last updated on 2026-06-17.

CVE-2020-13986

CVE-2020-13986 is a high-severity vulnerability in Contiki-os Contiki with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-835.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 3% (86th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-835
Affected product: Contiki-os Contiki
Published: 2020-12-11
Last modified: 2026-06-17

Description

An issue was discovered in Contiki through 3.0. An infinite loop exists in the uIP TCP/IP stack component when handling RPL extension headers of IPv6 network packets in rpl_remove_header in net/rpl/rpl-ext-header.c.

Frequently asked questions

What is CVE-2020-13986?: An issue was discovered in Contiki through 3.0. An infinite loop exists in the uIP TCP/IP stack component when handling RPL extension headers of IPv6 network packets in rpl_remove_header in net/rpl/rpl-ext-header.c.
How severe is CVE-2020-13986?: CVE-2020-13986 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2020-13986 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-13986?: CVE-2020-13986 affects Contiki-os Contiki. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-13986?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2020-13986 published?: CVE-2020-13986 was published on 2020-12-11 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:contiki-os:contiki:*:*:*:*:*:*:*:*

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