#VU73829 State Issues in cURL - CVE-2023-27536

Vulnerability identifier: #VU73829

Vulnerability risk: Medium

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

CVE-ID: CVE-2023-27536

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 otherwise restricted functionality.

The vulnerability exists due to cURL will reuse a previously created connection even when the GSS delegation (CURLOPT_GSSAPI_DELEGATION) option had been changed that could have changed the user's permissions in a second transfer. libcurl keeps previously used connections in a connection pool for subsequent transfers to reuse if one of them matches the setup. However, this GSS delegation setting was left out from the configuration match checks, making them match too easily, affecting krb5/kerberos/negotiate/GSSAPI transfers.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

cURL: 7.22.0 - 7.88.1

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External links
http://curl.haxx.se/docs/CVE-2023-27536.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.