CVE-2026-87865 in libcurl

Summary

by MITRE • 10/20/2026

When libcurl uses libssh2 with a hashed `known_hosts` file, an unrelated initial entry can cause host key validation to report a key *mismatch* as a *missing* key to the `CURLOPT_SSH_KEYFUNCTION` callback.

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• Responsible: Curl
• Reservation: 09/09/2026
• Disclosure: 10/20/2026
• Moderation: accepted
• Entry: VDB-423007
• CPE: 20261020
• CWE: CWE-295 (confirmed)
• CVSS: 3.7 (VulDB)
• EPSS: 0.00000
• KEV: no
• Activities: very low
• Sector: Hostingprovider, Chemical, ...

Sources

• MITRE: https://www.cve.org/CVERecord?id=CVE-2026-87865
• NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-87865
• CVE Details: https://www.cvedetails.com/cve/CVE-2026-87865/