CVE-2021-32780
"Envoy HTTP/2 Abnormal State Transition Denial of Service"
Description
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.
INFO
Published Date :
Aug. 24, 2021, 9:15 p.m.
Last Modified :
June 15, 2022, 3:48 p.m.
Source :
[email protected]
Remotely Exploitable :
Yes !
Impact Score :
4.0
Exploitability Score :
3.9
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2021-32780.
| URL | Resource |
|---|---|
| https://github.com/envoyproxy/envoy/security/advisories/GHSA-j374-mjrw-vvp8 | Third Party Advisory |
| https://www.envoyproxy.io/docs/envoy/v1.19.0/version_history/version_history | Vendor Advisory |
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2021-32780 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2021-32780 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by [email protected]
May. 14, 2024
Action Type Old Value New Value -
Reanalysis by [email protected]
Jun. 15, 2022
Action Type Old Value New Value Changed CPE Configuration OR *cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:* versions from (including) 1.18.0 up to (excluding) 1.18.4 *cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:* versions from (including) 1.19.0 up to (excluding) 1.91.1 OR *cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:* versions from (including) 1.18.0 up to (excluding) 1.18.4 *cpe:2.3:a:envoyproxy:envoy:1.19.0:*:*:*:*:*:*:* -
Initial Analysis by [email protected]
Aug. 31, 2021
Action Type Old Value New Value Added CVSS V2 NIST (AV:N/AC:L/Au:N/C:N/I:N/A:P) Added CVSS V3.1 NIST AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Changed Reference Type https://github.com/envoyproxy/envoy/security/advisories/GHSA-j374-mjrw-vvp8 No Types Assigned https://github.com/envoyproxy/envoy/security/advisories/GHSA-j374-mjrw-vvp8 Third Party Advisory Changed Reference Type https://www.envoyproxy.io/docs/envoy/v1.19.0/version_history/version_history No Types Assigned https://www.envoyproxy.io/docs/envoy/v1.19.0/version_history/version_history Vendor Advisory Added CWE NIST CWE-754 Added CPE Configuration OR *cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:* versions from (including) 1.18.0 up to (excluding) 1.18.4 *cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:* versions from (including) 1.19.0 up to (excluding) 1.91.1
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2021-32780 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2021-32780
weaknesses.
Exploit Prediction
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.
0.12 }} 0.01%
score
0.45228
percentile