CVE-2026-87865

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.

CVSS v3 7.4 HIGH

7.4^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://curl.se/docs/CVE-2026-87865.html
https://curl.se/docs/CVE-2026-87865.json
https://hackerone.com/reports/3975408
https://hackerone.com/reports/3975408

Configurations

No configuration.

History

30 Oct 2026, 12:16

Type	Values Removed	Values Added
CWE		CWE-295
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 7.4
References	~~() https://hackerone.com/reports/3975408 -~~	() https://hackerone.com/reports/3975408 -

20 Oct 2026, 21:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-20 21:17

Updated : 2026-10-30 12:16

NVD link : CVE-2026-87865

Mitre link : CVE-2026-87865

CVE.ORG link : CVE-2026-87865

JSON object : View

Products Affected

No product.

CWE

CWE-295

Improper Certificate Validation

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