How severe is CVE-2022-21655?

CVE-2022-21655 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-2022-21655 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (62nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2022-21655?

CVE-2022-21655 affects Envoyproxy Envoy. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2022-21655?

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-2022-21655 published?

CVE-2022-21655 was published on 2022-02-22 and last updated on 2026-06-17.

CVE-2022-21655

CVE-2022-21655 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-670.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 4.3
EPSS exploit prediction: 1% (62nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-670
Affected product: Envoyproxy Envoy
Published: 2022-02-22
Last modified: 2026-06-17

Description

Envoy is an open source edge and service proxy, designed for cloud-native applications. The envoy common router will segfault if an internal redirect selects a route configured with direct response or redirect actions. This will result in a denial of service. As a workaround turn off internal redirects if direct response entries are configured on the same listener.

Frequently asked questions

What is CVE-2022-21655?: Envoy is an open source edge and service proxy, designed for cloud-native applications. The envoy common router will segfault if an internal redirect selects a route configured with direct response or redirect actions. This will result in a denial of service. As a workaround turn off internal redirects if direct response entries are configured on the same listener.
How severe is CVE-2022-21655?: CVE-2022-21655 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-2022-21655 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (62nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2022-21655?: CVE-2022-21655 affects Envoyproxy Envoy. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2022-21655?: 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-2022-21655 published?: CVE-2022-21655 was published on 2022-02-22 and last updated on 2026-06-17.

References

Affected products (1)

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

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