Vulnerability identifier: #VU46682

Vulnerability risk: Medium

CVSSv3.1: 6.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2020-15166

CWE-ID: CWE-399

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
zeromq
Other software / Other software solutions

Vendor: www.zeromq.org

Description

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

The vulnerability exists due to improper management of internal resources with the application when processing TCP requests. If a raw TCP socket is opened and connected to an endpoint that is fully configured with CURVE/ZAP, legitimate clients will not be able to exchange any message. Handshakes complete successfully, and messages are delivered to the library, but the server application never receives them.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

zeromq: 4.0.6 - 4.3.2

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External links
http://github.com/zeromq/libzmq/pull/3913
http://github.com/zeromq/libzmq/pull/3973
http://github.com/zeromq/libzmq/security/advisories/GHSA-25wp-cf8g-938m
http://security.gentoo.org/glsa/202009-12

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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.