#VU57054 Input validation error in Zulip Server - CVE-2021-41115

Vulnerability identifier: #VU57054

Vulnerability risk: Low

CVSSv4.0: 4.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-41115

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Zulip Server
Web applications / Other software

Vendor: Zulip

Description

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

The vulnerability exists due to insufficient validation of user-supplied input within linkifier patterns. A remote administrator can pass specially crafted input to the application and perform a denial of service (DoS) attack.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Zulip Server: 4.0 - 4.6

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External links
https://github.com/zulip/zulip/releases/tag/4.7

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Q & A

Can this vulnerability be exploited remotely?

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

Is there known malware, which exploits this vulnerability?

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