How severe is CVE-2020-8663?

CVE-2020-8663 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-2020-8663 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (71st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-8663?

CVE-2020-8663 affects Envoyproxy Envoy. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-8663?

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-2020-8663 published?

CVE-2020-8663 was published on 2020-07-01 and last updated on 2026-06-17.

CVE-2020-8663

CVE-2020-8663 is a high-severity vulnerability in Envoyproxy Envoy 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-400.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 1% (71st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-400
Affected product: Envoyproxy Envoy
Published: 2020-07-01
Last modified: 2026-06-17

Description

Envoy version 1.14.2, 1.13.2, 1.12.4 or earlier may exhaust file descriptors and/or memory when accepting too many connections.

Frequently asked questions

What is CVE-2020-8663?: Envoy version 1.14.2, 1.13.2, 1.12.4 or earlier may exhaust file descriptors and/or memory when accepting too many connections.
How severe is CVE-2020-8663?: CVE-2020-8663 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-2020-8663 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (71st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-8663?: CVE-2020-8663 affects Envoyproxy Envoy. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-8663?: 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-2020-8663 published?: CVE-2020-8663 was published on 2020-07-01 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*

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