Is CVE-2023-27535 being actively exploited?

CVE-2023-27535 is not currently listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

What is the CVSS score for CVE-2023-27535?

CVE-2023-27535 has a CVSS 3.1 base score of 5.9 (MEDIUM).

CVE-2023-27535

MEDIUM · CVSS 5.9EPSS 1.8%EU EUVD

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.

Key facts

CVSS score: 5.9 (v3.1)
Severity: MEDIUM
CVSS vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
Weakness (CWE): CWE-305
EPSS score: 1.8% (78th percentile)
In CISA KEV: No
In EU EUVD: Yes (EUVD-2023-31290)
Published: March 30, 2023
NVD last modified: October 14, 2026
Status: Modified

EU Vulnerability Database (EUVD)

This vulnerability is also tracked by ENISA as EUVD-2023-31290 in the EU Vulnerability Database. Last updated in EUVD on October 14, 2026.

View on the EU Vulnerability Database

Affected products

debian / debian linux
fedoraproject / fedora
haxx / libcurl
netapp / active iq unified manager
netapp / h300s
netapp / h300s firmware
netapp / h410s
netapp / h410s firmware
netapp / h500s
netapp / h500s firmware
netapp / h700s
netapp / h700s firmware
netapp / ontap 9
splunk / universal forwarder
splunk / universal forwarder

Certified products that may be affected

4 FIPS 140 or Common Criteria certified products, from automated matching by sec-certs.org.

NetApp Volume Encryption (NVE) Appliances running ONTAP 9.14.1 - NetApp, Inc. - Common Criteria CCEVS-VR-VID-11475-2024 - active
NetApp Storage Encryption (NSE) Running ONTAP 9.14.1 - NetApp, Inc. - Common Criteria CCEVS-VR-VID-11477-2024 - active
NetApp Volume Encryption (NVE) Appliances running ONTAP 9.7P13 - NetApp, Inc. - Common Criteria CCEVS-VR-VID-11175-2021 - archived
NetApp Storage Encryption (NSE) running ONTAP 9.7P13 - NetApp, Inc. - Common Criteria CCEVS-VR-VID-11174-2021 - archived

References

https://cert-portal.siemens.com/productcert/html/ssa-398330.html
https://cert-portal.siemens.com/productcert/html/ssa-806742.html
https://cert-portal.siemens.com/productcert/html/ssa-943925.html
https://hackerone.com/reports/1892780(Exploit, Third Party Advisory)
https://lists.debian.org/debian-lts-announce/2023/04/msg00025.html(Mailing 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/202310-12(Third Party Advisory)
https://security.netapp.com/advisory/ntap-20230420-0010/(Third Party Advisory)

Last updated October 16, 2026 · Source: NVD, CISA KEV, FIRST.org EPSS

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