NULL Pointer Dereference Affecting envoyproxy/envoy package, versions [,1.35.13)[1.36.0,1.36.9)[1.37.0,1.37.5)[1.38.0,1.38.3)
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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- published28 Jun 2026
- disclosed26 Jun 2026
- creditUnknown
Introduced: 26 Jun 2026
CVE-2026-47221 (opens in a new tab)How to fix?
Upgrade envoyproxy/envoy to version 1.35.13, 1.36.9, 1.37.5, 1.38.3 or higher.
Overview
Affected versions of this package are vulnerable to NULL Pointer Dereference in the router filter when processing internal redirects for HTTP 303 responses to body-less non-GET/HEAD requests. An attacker can cause the process to crash and terminate all active connections by sending a POST, PUT, DELETE, or PATCH request without a body to a route configured with an internal redirect policy that includes 303 in redirect_response_codes, and triggering an upstream HTTP 303 response. This is only exploitable if the route is configured with an internal redirect policy that includes 303 in redirect_response_codes and the upstream returns an HTTP 303 response.