How severe is CVE-2020-8660?

CVE-2020-8660 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2020-8660 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (45th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-8660?

CVE-2020-8660 affects Envoyproxy Envoy. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-8660?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2020-8660 published?

CVE-2020-8660 was published on 2020-03-04 and last updated on 2026-06-17.

CVE-2020-8660

CVE-2020-8660 is a medium-severity vulnerability in Envoyproxy Envoy with a CVSS 3.x base score of 5.3. 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-345.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 5.0
EPSS exploit prediction: 1% (45th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-345
Affected product: Envoyproxy Envoy
Published: 2020-03-04
Last modified: 2026-06-17

Description

CNCF Envoy through 1.13.0 TLS inspector bypass. TLS inspector could have been bypassed (not recognized as a TLS client) by a client using only TLS 1.3. Because TLS extensions (SNI, ALPN) were not inspected, those connections might have been matched to a wrong filter chain, possibly bypassing some security restrictions in the process.

Frequently asked questions

What is CVE-2020-8660?: CNCF Envoy through 1.13.0 TLS inspector bypass. TLS inspector could have been bypassed (not recognized as a TLS client) by a client using only TLS 1.3. Because TLS extensions (SNI, ALPN) were not inspected, those connections might have been matched to a wrong filter chain, possibly bypassing some security restrictions in the process.
How severe is CVE-2020-8660?: CVE-2020-8660 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2020-8660 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (45th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-8660?: CVE-2020-8660 affects Envoyproxy Envoy. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-8660?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-8660 published?: CVE-2020-8660 was published on 2020-03-04 and last updated on 2026-06-17.

References

Affected products (1)

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

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