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7.5
HIGH CVSS 3.1
CVE-2021-43824
Null pointer dereference in envoy
Description

Envoy is an open source edge and service proxy, designed for cloud-native applications. In affected versions a crafted request crashes Envoy when a CONNECT request is sent to JWT filter configured with regex match. This provides a denial of service attack vector. The only workaround is to not use regex in the JWT filter. Users are advised to upgrade.

INFO

Published Date :

Feb. 22, 2022, 11:15 p.m.

Last Modified :

Nov. 21, 2024, 6:29 a.m.

Remotely Exploit :

Yes !

Source :

[email protected]
Affected Products

The following products are affected by CVE-2021-43824 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Envoyproxy envoy
: Total Affected Vendor : 1 | Products : 1
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 2.0 MEDIUM [email protected]
CVSS 3.1 HIGH [email protected]
CVSS 3.1 HIGH [email protected]
Solution
A denial of service vulnerability exists in Envoy when a crafted request is sent to the JWT filter configured with regex match.
  • Upgrade the Envoy package to a version that addresses this vulnerability.
  • Update the Red Hat OpenShift Service Mesh package based on the vendor guidance.
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-2021-43824.

URL Resource
https://github.com/envoyproxy/envoy/commit/9371333230b1a6e1be2eccf4868771e11af6253a Patch Third Party Advisory
https://github.com/envoyproxy/envoy/security/advisories/GHSA-vj5m-rch8-5r2p Issue Tracking Third Party Advisory
https://github.com/envoyproxy/envoy/commit/9371333230b1a6e1be2eccf4868771e11af6253a Patch Third Party Advisory
https://github.com/envoyproxy/envoy/security/advisories/GHSA-vj5m-rch8-5r2p Issue Tracking Third Party Advisory
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2021-43824 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-2021-43824 weaknesses.

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-2021-43824 vulnerability anywhere in the article.

Results are limited to the first 20 news articles due to potential performance issues.

The following table lists the changes that have been made to the CVE-2021-43824 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 af854a3a-2127-422b-91ae-364da2661108

    Nov. 21, 2024

    Action Type Old Value New Value
    Added Reference https://github.com/envoyproxy/envoy/commit/9371333230b1a6e1be2eccf4868771e11af6253a
    Added Reference https://github.com/envoyproxy/envoy/security/advisories/GHSA-vj5m-rch8-5r2p
  • CVE Modified by [email protected]

    May. 14, 2024

    Action Type Old Value New Value
  • Initial Analysis by [email protected]

    Mar. 01, 2022

    Action Type Old Value New Value
    Added CVSS V2 NIST (AV:N/AC:M/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/commit/9371333230b1a6e1be2eccf4868771e11af6253a No Types Assigned https://github.com/envoyproxy/envoy/commit/9371333230b1a6e1be2eccf4868771e11af6253a Patch, Third Party Advisory
    Changed Reference Type https://github.com/envoyproxy/envoy/security/advisories/GHSA-vj5m-rch8-5r2p No Types Assigned https://github.com/envoyproxy/envoy/security/advisories/GHSA-vj5m-rch8-5r2p Issue Tracking, Third Party Advisory
    Added CPE Configuration OR *cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:* versions up to (excluding) 1.18.6 *cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:* versions from (including) 1.19.0 up to (excluding) 1.19.3 *cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:* versions from (including) 1.20.0 up to (excluding) 1.20.2 *cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:* versions from (including) 1.21.0 up to (excluding) 1.21.1
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
Vulnerability Scoring Details
Base CVSS Score: 7.5
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality Impact
Integrity Impact
Availability Impact
Base CVSS Score: 4.3
Access Vector
Access Complexity
Authentication
Confidentiality Impact
Integrity Impact
Availability Impact
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

0.32441

percentile