CVE-2020-27638
CVE-2020-27638 is a high-severity vulnerability in Fastd Project Fastd 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-617.
Key facts
- Severity: High (CVSS 3.x base score 7.5)
- CVSS v2: 5.0
- EPSS exploit prediction: 2% (82nd percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-617
- Affected product: Fastd Project Fastd
- Published:
- Last modified:
Description
receive.c in fastd before v21 allows denial of service (assertion failure) when receiving packets with an invalid type code.
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 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-2020-27638 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (82nd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2020-27638?
- CVE-2020-27638 primarily affects Fastd Project Fastd. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2020-27638?
- 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-2020-27638 published?
- CVE-2020-27638 was published on 2020-10-22 and last updated on 2026-06-17.
References
- https://bugs.debian.org/972521
- https://fastd.readthedocs.io/en/stable/releases/v21.html
- https://github.com/NeoRaider/fastd/commit/737925113363b6130879729cdff9ccc46c33eaea
- https://lists.debian.org/debian-lts-announce/2020/10/msg00025.html
- 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/
Affected products (5)
- cpe:2.3:a:fastd_project:fastd:*:*:*:*:*:*:*:*
- cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
- cpe:2.3:o:fedoraproject:fedora:31:*:*:*:*:*:*:*
- cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:*
- cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*
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- CVE-2026-31739 — High (CVSS 8.8): In the Linux kernel, the following vulnerability has been resolved: crypto: tegra - Add missing CRYPTO_ALG_ASYNC The…
- CVE-2020-12417 — High (CVSS 8.8): Due to confusion about ValueTags on JavaScript Objects, an object may pass through the type barrier, resulting in…
- CVE-2020-6623 — High (CVSS 8.8): stb stb_truetype.h through 1.22 has an assertion failure in stbtt__cff_get_index.
- CVE-2020-6619 — High (CVSS 8.8): stb stb_truetype.h through 1.22 has an assertion failure in stbtt__buf_seek.