CVE-2026-47207

Envoy crashes if multiple unexpected ext_proc responses are packed into one gRPC message

Description

Envoy is an open source edge and service proxy designed for cloud-native applications. From 1.34.0 until 1.35.13, 1.36.9, 1.37.5, and 1.38.3, Envoy crashes if an ext_proc server sends a single gRPC message containing multiple, specially crafted ProcessingResponse messages. This can occur when the first response in the batch causes the gRPC stream object to be destroyed, leading to a use-after-free error when Envoy attempts to process subsequent responses in the same gRPC message. This vulnerability is fixed in 1.35.13, 1.36.9, 1.37.5, and 1.38.3.

Scores

Weaknesses (CWE)

• CWE-416

European references

• ENISA EUVD · EUVD-2026-39826
• GCVE · GCVE-0-2026-47207

Affected configurations (NVD CPE)

• cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:* ≥ 1.34.0 < 1.35.13
• cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:* ≥ 1.36.0 < 1.36.9
• cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:* ≥ 1.37.0 < 1.37.5
• cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:* ≥ 1.38.0 < 1.38.3

Affected products

References

• https://github.com/envoyproxy/envoy/security/advisories/GHSA-68cv-hq5f-g6xv

Sources