Vulnerability record · CVE-2023-27538 · published 30 March 2023
CVE-2023-27538: Haxx libcurl improper authentication vulnerability
Haxx · Libcurl
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.
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.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Affected products
11 vulnerable configurations from NVD's CPE data, grouped by vendor and product.
References
| Link | Tags |
|---|---|
| https://hackerone.com/reports/1898475 | ExploitThird Party Advisory |
| https://lists.debian.org/debian-lts-announce/2023/04/msg00025.html | Mailing List |
| https://security.gentoo.org/glsa/202310-12 | Third Party Advisory |
| https://security.netapp.com/advisory/ntap-20230420-0010/ | Third Party Advisory |
| https://hackerone.com/reports/1898475 | ExploitThird Party Advisory |
| https://lists.debian.org/debian-lts-announce/2023/04/msg00025.html | Mailing List |
| https://security.gentoo.org/glsa/202310-12 | Third Party Advisory |
| https://security.netapp.com/advisory/ntap-20230420-0010/ | Third Party Advisory |
Track CVE-2023-27538 inside VULONE
Watch it alongside the ransomware crews, C2 infrastructure and forum chatter that reference it, query it through the API and pull it into your SIEM over TAXII.
Related vulnerabilities
Same products first, then exploited flaws of the same weakness class.
Source: NIST National Vulnerability Database (record CVE-2023-27538), CISA KEV, FIRST EPSS (scores of 2026-09-29). This page is refreshed as NVD updates the record.
