#VU56244 Resource exhaustion in eventlet - CVE-2021-21419

Vulnerability identifier: #VU56244

Vulnerability risk: Medium

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

CVE-ID: CVE-2021-21419

CWE-ID: CWE-400

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
eventlet
Universal components / Libraries / Libraries used by multiple products

Vendor: eventlet.net

Description

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

The vulnerability exists due to application does not properly control consumption of internal resources when handling large websocket frames. A remote attacker can trigger resource exhaustion by sending highly compressed data frame and perform a denial of service (DoS) attack.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

eventlet: 0.9.16 - 0.30.3

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External links
https://github.com/eventlet/eventlet/security/advisories/GHSA-9p9m-jm8w-94p2
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/R5JZP4LZOSP7CUAM3GIRW6PIAWKH5VGB/
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/2WJFSBPLCNSZNHYQC4QDRDFRTEZRMD2L/

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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.