CVE-2021-43824: Null pointer dereference in envoy

Published Feb 4, 2022
·
Updated

A flaw was found in envoy. A crafted request can potentially trigger a NULL pointer dereference when using a WT filter saferegex match.

Other sources

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.

Potential null pointer dereference when using JWT filter saferegex match.

Red Hat

Affected Software

10 affected componentsFixes available
redhat/servicemesh-proxy<0:2.0.9-3.el8
0:2.0.9-3.el8
redhat/servicemesh-proxy<0:2.1.2-4.el8
0:2.1.2-4.el8
redhat/envoy<1.18.6
1.18.6
redhat/envoy<1.19.3
1.19.3
redhat/envoy<1.20.2
1.20.2
redhat/envoy<1.21.1
1.21.1
Envoyproxy Envoy<1.18.6
Envoyproxy Envoy>=1.19.0<1.19.3
Envoyproxy Envoy>=1.20.0<1.20.2
Envoyproxy Envoy>=1.21.0<1.21.1

Event History

Feb 22, 2022
CVE Published
07:00 AM
CVE Published
via MITRE·10:15 PM
Data Sourced
via MITRE·10:15 PM
DescriptionSeverityWeakness

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

What is CVE-2021-43824?

CVE-2021-43824 is a vulnerability found in Envoy that can trigger a NULL pointer dereference and cause a denial of service attack.

2

How does CVE-2021-43824 affect Envoy?

CVE-2021-43824 affects Envoy when a CONNECT request is sent to the JWT filter configured with regex match, causing Envoy to crash.

3

What is the severity of CVE-2021-43824?

CVE-2021-43824 has a severity rating of high.

4

How can I fix CVE-2021-43824?

To fix CVE-2021-43824, you should update to the latest version of Envoy or servicemesh-proxy that includes the necessary fixes.

5

Where can I find more information about CVE-2021-43824?

You can find more information about CVE-2021-43824 on the official CVE page, NVD, GitHub security advisories, Bugzilla, and Red Hat errata.

Contact

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