How severe is CVE-2024-23327?

CVE-2024-23327 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-2024-23327 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (48th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2024-23327?

CVE-2024-23327 affects Envoyproxy Envoy. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2024-23327?

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.

Does CVE-2024-23327 have an EU (EUVD) identifier?

Yes. CVE-2024-23327 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-20842.

When was CVE-2024-23327 published?

CVE-2024-23327 was published on 2024-02-09 and last updated on 2026-06-17.

CVE-2024-23327

CVE-2024-23327 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-476.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (48th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2024-20842
Weakness: CWE-476
Affected product: Envoyproxy Envoy
Published: 2024-02-09
Last modified: 2026-06-17

Description

Envoy is a high-performance edge/middle/service proxy. When PPv2 is enabled both on a listener and subsequent cluster, the Envoy instance will segfault when attempting to craft the upstream PPv2 header. This occurs when the downstream request has a command type of LOCAL and does not have the protocol block. This issue has been addressed in releases 1.29.1, 1.28.1, 1.27.3, and 1.26.7. Users are advised to upgrade. There are no known workarounds for this vulnerability.

Frequently asked questions

What is CVE-2024-23327?: Envoy is a high-performance edge/middle/service proxy. When PPv2 is enabled both on a listener and subsequent cluster, the Envoy instance will segfault when attempting to craft the upstream PPv2 header. This occurs when the downstream request has a command type of LOCAL and does not have the protocol block. This issue has been addressed in releases 1.29.1, 1.28.1, 1.27.3, and 1.26.7. Users are advised to upgrade. There are no known workarounds for this vulnerability.
How severe is CVE-2024-23327?: CVE-2024-23327 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-2024-23327 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (48th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2024-23327?: CVE-2024-23327 affects Envoyproxy Envoy. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2024-23327?: 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.
Does CVE-2024-23327 have an EU (EUVD) identifier?: Yes. CVE-2024-23327 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-20842.
When was CVE-2024-23327 published?: CVE-2024-23327 was published on 2024-02-09 and last updated on 2026-06-17.

References

Affected products (1)

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

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