Improper Certificate Validation Affecting curl package, versions [7.43.0,8.23.0)
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.
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Test your applications- Snyk IDSNYK-UNMANAGED-CURL-21195661
- published18 Oct 2026
- disclosed14 Oct 2026
- creditUnknown
Introduced: 14 Oct 2026
NewCVE-2026-87866 (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 Improper Certificate Validation in the wolfSSL backend during the TLS handshake process. An attacker can cause improper authorization of an invalid key by presenting a specially crafted certificate with a manipulated validity length field. This is only exploitable if the application is linked against a wolfSSL-backed build and pinned public key verification is enabled.