Use-after-free in envoy - CVE-2026-47205
Published: June 24, 2026
Vulnerability identifier: #VU135108
CSH Severity: Medium
CVSS v4: 8.2 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-47205
CWE-ID: CWE-416
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to use-after-free in the ext_authz HTTP filter when processing per-route authorization overrides concurrently with rapid downstream client disconnects. A remote attacker can rapidly create and tear down streams to cause a denial of service.
Exploitation requires the target route to use a per-route ext_authz override with grpc_service or http_service, and the disconnect must occur during the authorization check interval.
Affected software
envoy
How to mitigate CVE-2026-47205
Install security update from vendor's website.
envoy - addressed in versions 1.35.12, 1.36.8, 1.37.4, 1.38.2