#VU56273 Improper Authorization in Eclipse Mosquitto - CVE-2021-34434

Vulnerability identifier: #VU56273

Vulnerability risk: Medium

CVSSv4.0: 2.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-34434

CWE-ID: CWE-285

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Eclipse Mosquitto
Server applications / Other server solutions

Vendor: Eclipse

Description

The vulnerability allows a remote attacker to bypass authorization checks.

The vulnerability exists due to a subscriptions revoke flaw when using the dynamic security plugin. A remote attacker can send a specially crafted request and obtain subscriptions information.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Eclipse Mosquitto: 2.0.0 - 2.0.11

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External links
https://bugs.eclipse.org/bugs/show_bug.cgi?id=575324

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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.