Vulnerability identifier: #VU80033

Vulnerability risk: Medium

CVSSv3.1: 5.7 [CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-41803

CWE-ID: CWE-862

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Consul
Server applications / Other server solutions
Consul Enterprise
Server applications / Other server solutions

Vendor: HashiCorp

Description

The vulnerability allows a remote user to perform a denial of service (DoS) attack.

The vulnerability exists due to improper input validation when handling auto-config requests. A remote authenticated user can craft an auto-config request that allows the TLS certificate and ACL token to be generated for a node name not intended by the operator. This forces Consul to store unintended information, which can be repeatedly abused to cause an authenticated denial of service attack from a malicious operator.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Consul: 1.13.0 - 1.13.1, 1.12.0 - 1.12.4, 1.11.0 - 1.11.8, 1.10.0 - 1.10.12, 1.9.0 - 1.9.17, 1.8.1 - 1.8.19

Consul Enterprise: 1.13.0 - 1.13.1, 1.12.0 - 1.12.4, 1.11.0 - 1.11.8, 1.10.0 - 1.10.12, 1.9.0 - 1.9.17, 1.8.1 - 1.8.19

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External links
http://discuss.hashicorp.com/t/hcsec-2022-19-consul-auto-config-jwt-authorization-missing-input-validation/44627

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.