CVE-2021-32781

Continued processing of requests after locally generated response

Description

Envoy is an open source L7 proxy and communication bus designed for large modern service oriented architectures. In affected versions after Envoy sends a locally generated response it must stop further processing of request or response data. However when local response is generated due the internal buffer overflow while request or response is processed by the filter chain the operation may not be stopped completely and result in accessing a freed memory block. A specifically constructed request delivered by an untrusted downstream or upstream peer in the presence of extensions that modify and increase the size of request or response bodies resulting in a Denial of Service when using extensions that modify and increase the size of request or response bodies, such as decompressor filter. Envoy versions 1.19.1, 1.18.4, 1.17.4, 1.16.5 contain fixes to address incomplete termination of request processing after locally generated response. As a workaround disable Envoy's decompressor, json-transcoder or grpc-web extensions or proprietary extensions that modify and increase the size of request or response bodies, if feasible.

Categories

8.6
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.08%
Vendor Advisory envoyproxy.io
Affected: envoyproxy envoy
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2021-32781?
CVE-2021-32781 has been scored as a high severity vulnerability.
How to fix CVE-2021-32781?
To fix CVE-2021-32781, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-32781 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-32781 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-32781?
CVE-2021-32781 affects envoyproxy envoy.
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