CVE-2023-27538

Name: CVE-2023-27538
Creator: NVD / NIST
Published: 2023-03-30T20:15:07.677+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.5/10EPSS 1.16%

Last modified Jun 17, 2026

CVE-2023-27538 is a medium-severity vulnerability rated 5.5/10 on the CVSS scale. An authentication bypass vulnerability exists in libcurl prior to v8.0.0 where it reuses a previously established SSH connection despite the fact that an SSH option was modified, which should have prevented reuse. libcurl maintains a pool of previously used connections to reuse them for subsequent transfers if the configurations match. EPSS estimates a 1.16% chance of exploitation in the next 30 days.

Description

An authentication bypass vulnerability exists in libcurl prior to v8.0.0 where it reuses a previously established SSH connection despite the fact that an SSH option was modified, which should have prevented reuse. libcurl maintains a pool of previously used connections to reuse them for subsequent transfers if the configurations match. However, two SSH settings were omitted from the configuration check, allowing them to match easily, potentially leading to the reuse of an inappropriate connection.

Metrics

CVSS 3.1

5.5/10

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

EPSS Probability

1.16%

63.2th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Haxx	Libcurl	>= 7.16.1, < 8.0.0
Fedoraproject	Fedora	36
Debian	Debian Linux	10.0
Netapp	Active Iq Unified Manager	All versions
Netapp	Clustered Data Ontap	9.0
Broadcom	Brocade Fabric Operating System Firmware	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/1898475Exploit, Third Party Advisory
https://lists.debian.org/debian-lts-announce/2023/04/msg00025.htmlMailing List
https://security.gentoo.org/glsa/202310-12Third Party Advisory
https://security.netapp.com/advisory/ntap-20230420-0010/Third Party Advisory
https://hackerone.com/reports/1898475Exploit, Third Party Advisory
https://lists.debian.org/debian-lts-announce/2023/04/msg00025.htmlMailing List
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-2023-27538?

How severe is CVE-2023-27538?

CVE-2023-27538 has a CVSS score of 5.5/10 (MEDIUM severity). The EPSS model estimates a 1.16% probability of exploitation in the next 30 days.

How do I fix CVE-2023-27538?

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-2023-27538?

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

Scan your code now

Source: NVD / NIST