Authentication Bypass by Primary Weakness Affecting curl package, versions [8.17.0,8.21.0)
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
Do your applications use this vulnerable package?
In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.
Test your applications- Snyk IDSNYK-UNMANAGED-CURL-17808151
- published3 Jul 2026
- disclosed3 Jul 2026
- creditUnknown
Introduced: 3 Jul 2026
NewCVE-2026-11564 (opens in a new tab)How to fix?
Upgrade curl to version 8.21.0 or higher.
Overview
curl is a command line tool and library for transferring data with URL syntax, supporting DICT, FILE, FTP, FTPS, GOPHER, GOPHERS, HTTP, HTTPS, IMAP, IMAPS, LDAP, LDAPS, MQTT, POP3, POP3S, RTMP, RTMPS, RTSP, SCP, SFTP, SMB, SMBS, SMTP, SMTPS, TELNET and TFTP. libcurl offers a myriad of powerful features.
Affected versions of this package are vulnerable to Authentication Bypass by Primary Weakness in the connection pool process. An attacker can bypass intended certificate validation by reusing a handle that initially used the default native CA trust and then switching it to custom CA material, causing subsequent transfers to continue trusting the native platform store.