Medium severity · published Jun 26, 2026
CVE-2026-47207
Envoy crashes if multiple unexpected ext_proc responses are packed into one gRPC message
6.5
CVSS
0.4%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 38% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
EN
envoy · envoyproxy
>= 1.38.0, < 1.38.3; >= 1.37.0, < 1.37.5; >= 1.36.0, < 1.36.9; >= 1.34.0, < 1.35.13 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-47207
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-47207
Exploit
https://github.com/envoyproxy/envoy/security/advisories/GHSA-68cv-hq5f-g6xv
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