title: Use-after-free in Envoy
description: Envoy is an open source edge and service proxy, designed for cloud-native applications. Sending a locally generated response must stop further processing of request or response data. Envoy tracks the amount of buffered request and response data and aborts the request if the amount of buffered data is over the limit by sending 413 or 500 responses. However when the buffer overflows while response is processed by the filter chain the operation may not be aborted correctly and result in accessing a freed memory block. If this happens Envoy will crash resulting in a denial of service.
problem types: CWE-416: Use After Free
affected:
{
product: envoy
vendor: envoyproxy
versions:
status: affected, version: < 1.18.6
status: affected, version: >= 1.19.0, < 1.19.3
status: affected, version: >= 1.20.0, < 1.20.2
status: affected, version: >= 1.21.0, < 1.21.1
}
metrics:
cvssV3_1: [
attackComplexity: LOW
attackVector: NETWORK
availabilityImpact: LOW
baseScore: 6.1
baseSeverity: MEDIUM
confidentialityImpact: NONE
integrityImpact: LOW
privilegesRequired: NONE
scope: CHANGED
userInteraction: REQUIRED
vectorString: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:L/A:L
version: 3.1
]