Vulnerability identifier: #VU73828

Vulnerability risk: Low

CVSSv3.1: 4.2 [CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2023-27535

CWE-ID: CWE-371

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
cURL
Client/Desktop applications / Other client software

Vendor: curl.haxx.se

Description

The vulnerability allows a remote attacker to gain unauthorized access to FTP server.

The vulnerability exists due to cURL will reuse a previously created FTP connection even when one or more options had been changed that could have made the effective user a very different one. A remote attacker can connect to the FTP server using credentials supplied by another user and gain access to otherwise restricted functionality.

The settings in questions are CURLOPT_FTP_ACCOUNT, CURLOPT_FTP_ALTERNATIVE_TO_USER, CURLOPT_FTP_SSL_CCC and CURLOPT_USE_SSL level.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

cURL: 7.13.0 - 7.88.1

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External links
http://curl.haxx.se/docs/CVE-2023-27535.html

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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.