High severity · published Feb 22, 2022
CVE-2021-43824
Envoy is an open source edge and service proxy, designed for cloud-native applications
7.5
CVSS
1.1%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.1% · higher than 64% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
EN
Envoy · Envoyproxy
before 1.18.6; 1.19.0 before 1.19.3; 1.20.0 before 1.20.2; 1.21.0 before 1.21.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-43824
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-43824
Patch
https://github.com/envoyproxy/envoy/commit/9371333230b1a6e1be2eccf4868771e11af6253a
Issue Tracking
https://github.com/envoyproxy/envoy/security/advisories/GHSA-vj5m-rch8-5r2p
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