CVE-2021-43825
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.
How to fix CVE-2021-43825
To remediate CVE-2021-43825, upgrade the affected package to a fixed version below.
- —upgrade to 1.18.6 or later
Is CVE-2021-43825 being exploited?
Low — EPSS is 0.1%, meaning exploitation activity has not been observed at scale.
Affected packages (1)
- from 0, < 1.18.6, >= 1.19.0, < 1.19.3, >= 1.20.0, < 1.20.2, >= 1.21.0, < 1.21.1
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | HIGH7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |