Vulnerability Details : CVE-2021-32781
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.
Vulnerability category: OverflowDenial of service
Products affected by CVE-2021-32781
- cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*
- cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*
- cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*
- cpe:2.3:a:envoyproxy:envoy:1.19.0:*:*:*:*:*:*:*
Exploit prediction scoring system (EPSS) score for CVE-2021-32781
0.12%
Probability of exploitation activity in the next 30 days
EPSS Score History
~ 45 %
Percentile, the proportion of vulnerabilities that are scored at or less
CVSS scores for CVE-2021-32781
Base Score | Base Severity | CVSS Vector | Exploitability Score | Impact Score | Score Source | First Seen |
---|---|---|---|---|---|---|
5.0
|
MEDIUM | AV:N/AC:L/Au:N/C:N/I:N/A:P |
10.0
|
2.9
|
NIST | |
7.5
|
HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
3.9
|
3.6
|
NIST | |
8.6
|
HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H |
3.9
|
4.0
|
GitHub, Inc. |
CWE ids for CVE-2021-32781
-
The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow.Assigned by: nvd@nist.gov (Primary)
-
The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.Assigned by: security-advisories@github.com (Secondary)
References for CVE-2021-32781
-
https://github.com/envoyproxy/envoy/security/advisories/GHSA-5vhv-gp9v-42qv
Continued processing of requests after locally generated response · Advisory · envoyproxy/envoy · GitHubThird Party Advisory
-
https://www.envoyproxy.io/docs/envoy/v1.19.0/version_history/version_history
Version history — envoy tag-v1.19.0 documentationVendor Advisory
Jump to