Insertion of Sensitive Information Into Sent Data Affecting curl package, versions [8.21.0,8.23.0)
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-21195798
- published18 Oct 2026
- disclosed14 Oct 2026
- creditUnknown
Introduced: 14 Oct 2026
NewCVE-2026-87861 (opens in a new tab)How to fix?
Upgrade curl to version 8.23.0 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 Insertion of Sensitive Information Into Sent Data in the process handling Negotiate authentication with ambient credentials. An attacker can obtain sensitive information by causing requests intended for one server to be sent over an authenticated connection to a different server origin. This is only exploitable if applications multiplex requests across different origins while relying on blank user identities for Kerberos or SPNEGO authentication.