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.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.12%
Third-Party Advisory github.com Third-Party Advisory github.com
Affected: envoyproxy envoy
Published at:
Updated at:

References

Link Tags
https://github.com/envoyproxy/envoy/security/advisories/GHSA-vj5m-rch8-5r2p third party advisory issue tracking
https://github.com/envoyproxy/envoy/commit/9371333230b1a6e1be2eccf4868771e11af6253a third party advisory patch

Frequently Asked Questions

What is the severity of CVE-2021-43824?
CVE-2021-43824 has been scored as a high severity vulnerability.
How to fix CVE-2021-43824?
To fix CVE-2021-43824, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-43824 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-43824 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-43824?
CVE-2021-43824 affects envoyproxy envoy.
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