CVE-2023-27535

Name: CVE-2023-27535
Creator: NVD / NIST
Published: 2023-03-30T20:15:07.483+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.9/10EPSS 1.61%

Last modified Jun 17, 2026

CVE-2023-27535 is a medium-severity vulnerability rated 5.9/10 on the CVSS scale. An authentication bypass vulnerability exists in libcurl <8.0.0 in the FTP connection reuse feature that can result in wrong credentials being used during subsequent transfers. Previously created connections are kept in a connection pool for reuse if they match the current setup. EPSS estimates a 1.61% chance of exploitation in the next 30 days.

Description

An authentication bypass vulnerability exists in libcurl <8.0.0 in the FTP connection reuse feature that can result in wrong credentials being used during subsequent transfers. Previously created connections are kept in a connection pool for reuse if they match the current setup. However, certain FTP settings such as CURLOPT_FTP_ACCOUNT, CURLOPT_FTP_ALTERNATIVE_TO_USER, CURLOPT_FTP_SSL_CCC, and CURLOPT_USE_SSL were not included in the configuration match checks, causing them to match too easily. This could lead to libcurl using the wrong credentials when performing a transfer, potentially allowing unauthorized access to sensitive information.

Metrics

CVSS 3.1

5.9/10

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

EPSS Probability

1.61%

72.8th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Haxx	Libcurl	>= 7.13.0, <= 7.88.1
Fedoraproject	Fedora	36
Debian	Debian Linux	10.0
Netapp	Active Iq Unified Manager	All versions
Netapp	Ontap 9	All versions
Netapp	H300s Firmware	All versions
Netapp	H500s Firmware	All versions
Netapp	H700s Firmware	All versions
Netapp	H410s Firmware	All versions
Splunk	Universal Forwarder	>= 8.2.0, < 8.2.12
Splunk	Universal Forwarder	>= 9.0.0, < 9.0.6
Splunk	Universal Forwarder	9.1.0

References

https://hackerone.com/reports/1892780Exploit, Third Party Advisory
https://lists.debian.org/debian-lts-announce/2023/04/msg00025.htmlMailing List, Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/36NBD5YLJXXEDZLDGNFCERWRYJQ6LAQW/Mailing List, Third Party Advisory
https://security.gentoo.org/glsa/202310-12Third Party Advisory
https://security.netapp.com/advisory/ntap-20230420-0010/Third Party Advisory
https://hackerone.com/reports/1892780Exploit, Third Party Advisory
https://lists.debian.org/debian-lts-announce/2023/04/msg00025.htmlMailing List, Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/36NBD5YLJXXEDZLDGNFCERWRYJQ6LAQW/Mailing List, Third Party Advisory
https://security.gentoo.org/glsa/202310-12Third Party Advisory
https://security.netapp.com/advisory/ntap-20230420-0010/Third Party Advisory

Timeline

Published: Mar 30, 2023
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2023-27535?

How severe is CVE-2023-27535?

CVE-2023-27535 has a CVSS score of 5.9/10 (MEDIUM severity). The EPSS model estimates a 1.61% probability of exploitation in the next 30 days.

How do I fix CVE-2023-27535?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2023-27535?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST