CVE-2020-27638

Name: CVE-2020-27638
Creator: NVD / NIST
Published: 2020-10-22T13:15:15.613+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 2.33%

Last modified Jun 17, 2026

CVE-2020-27638 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. receive.c in fastd before v21 allows denial of service (assertion failure) when receiving packets with an invalid type code.. EPSS estimates a 2.33% chance of exploitation in the next 30 days.

Description

receive.c in fastd before v21 allows denial of service (assertion failure) when receiving packets with an invalid type code.

Metrics

CVSS 3.1

7.5/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

2.33%

81.4th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-617

Affected Software

Vendor	Product	Versions
Fastd Project	Fastd	< 21.0
Debian	Debian Linux	9.0
Fedoraproject	Fedora	31
Fedoraproject	Fedora	32
Fedoraproject	Fedora	33

References

https://bugs.debian.org/972521Issue Tracking, Third Party Advisory
https://fastd.readthedocs.io/en/stable/releases/v21.htmlBroken Link, Release Notes, Third Party Advisory
https://github.com/NeoRaider/fastd/commit/737925113363b6130879729cdff9ccc46c33eaeaPatch, Third Party Advisory
https://lists.debian.org/debian-lts-announce/2020/10/msg00025.htmlMailing List, Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/D2LNSF2LI4RQ7BVGHTJQUJWP7RVGHDTK/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GUZ3AGTAXH7OOP45F5WXBVRQ3IDWUR7M/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WSMH65GHKHMJAK2VMPROIPIUS4IA63CW/
https://bugs.debian.org/972521Issue Tracking, Third Party Advisory
https://fastd.readthedocs.io/en/stable/releases/v21.htmlBroken Link, Release Notes, Third Party Advisory
https://github.com/NeoRaider/fastd/commit/737925113363b6130879729cdff9ccc46c33eaeaPatch, Third Party Advisory
https://lists.debian.org/debian-lts-announce/2020/10/msg00025.htmlMailing List, Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/D2LNSF2LI4RQ7BVGHTJQUJWP7RVGHDTK/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GUZ3AGTAXH7OOP45F5WXBVRQ3IDWUR7M/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WSMH65GHKHMJAK2VMPROIPIUS4IA63CW/

Timeline

Published: Oct 22, 2020
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-27638?

receive.c in fastd before v21 allows denial of service (assertion failure) when receiving packets with an invalid type code.

How severe is CVE-2020-27638?

CVE-2020-27638 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 2.33% probability of exploitation in the next 30 days.

How do I fix CVE-2020-27638?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2020-27638?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST