#VU36038 Security Features in Consul - CVE-2019-9764

Vulnerability identifier: #VU36038

Vulnerability risk: Medium

CVSSv4.0: 6.9 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2019-9764

CWE-ID: CWE-254

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Consul
Server applications / Other server solutions

Vendor: HashiCorp

Description

The vulnerability allows a remote non-authenticated attacker to read and manipulate data.

HashiCorp Consul 1.4.3 lacks server hostname verification for agent-to-agent TLS communication. In other words, the product behaves as if verify_server_hostname were set to false, even when it is actually set to true. This is fixed in 1.4.4.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Consul: 1.4.3

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External links
https://github.com/hashicorp/consul/issues/5519

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

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