CVE-2026-47221

[CVE catalog]

Severity

High · CVSS 7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Published

Jun 23, 2026, 10:00:00 PM UTC

Source

[NVD] · [CVE record]

EPSS

0.45% · Oct 25, 2026

A flaw was found in Envoy. An unauthenticated attacker can exploit a null pointer dereference vulnerability in the router filter. This occurs when handling HTTP 303 (See Other) internal redirects for body-less non-GET/HEAD requests. By sending a POST, PUT, DELETE, or PATCH request without a body to a specially configured route, and if the upstream responds with HTTP 303, the Envoy process will crash. This leads to a complete denial of service, terminating all active connections. envoy: Envoy: Null pointer deref in internal redirects Moderate: An unauthenticated attacker can trigger a denial of service in Envoy. This is due to a null pointer dereference when handling HTTP 303 internal redirects for body-less non-GET/HEAD requests, leading to a crash of the Envoy process. This vulnerability affects Envoy deployments configured with an internal redirect policy that includes HTTP 303 in `redirect_response_codes`. The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.