Vulnerability Details : CVE-2021-32780
Envoy is an open source L7 proxy and communication bus designed for large modern service oriented architectures. In affected versions Envoy transitions a H/2 connection to the CLOSED state when it receives a GOAWAY frame without any streams outstanding. The connection state is transitioned to DRAINING when it receives a SETTING frame with the SETTINGS_MAX_CONCURRENT_STREAMS parameter set to 0. Receiving these two frames in the same I/O event results in abnormal termination of the Envoy process due to invalid state transition from CLOSED to DRAINING. A sequence of H/2 frames delivered by an untrusted upstream server will result in Denial of Service in the presence of untrusted **upstream** servers. Envoy versions 1.19.1, 1.18.4 contain fixes to stop processing of pending H/2 frames after connection transition to the CLOSED state.
Vulnerability category: Denial of service
Products affected by CVE-2021-32780
- cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*
- cpe:2.3:a:envoyproxy:envoy:1.19.0:*:*:*:*:*:*:*
Exploit prediction scoring system (EPSS) score for CVE-2021-32780
0.08%
Probability of exploitation activity in the next 30 days
EPSS Score History
~ 20 %
Percentile, the proportion of vulnerabilities that are scored at or less
CVSS scores for CVE-2021-32780
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-2021-32780
-
The product does not check or incorrectly checks for unusual or exceptional conditions that are not expected to occur frequently during day to day operation of the product.Assigned by:
- nvd@nist.gov (Primary)
- security-advisories@github.com (Secondary)
References for CVE-2021-32780
-
https://www.envoyproxy.io/docs/envoy/v1.19.0/version_history/version_history
Version history — envoy tag-v1.19.0 documentationVendor Advisory
-
https://github.com/envoyproxy/envoy/security/advisories/GHSA-j374-mjrw-vvp8
Incorrect handling of H/2 GOAWAY followed by SETTINGS frames · Advisory · envoyproxy/envoy · GitHubThird Party Advisory
Jump to