Vulnerability Report

CVE-2026-12064

Title: curl SSH host verification bypass with schemeless URL

Other

Proof Of Concept

No public PoC currently indexed for CVE-2026-12064.

CWE Category NVD-CWE-noinfo
Published Date Jul 03, 2026
Modified Date Jul 07, 2026
Exploit Status Not Found
Score 7.5 CVSS v
Exploit Probability (EPSS)
0.57%

Vulnerability Summary

CVE-2026-12064: When a user invokes curl using a schemeless URL combined with `--proto-default` sftp (or scp), a disconnect occurs between the tool layer and libcurl. The tool layer incorrectly infers the URL scheme, which erroneously bypasses the initialization of critical SSH security options like CURLOPT_SSH_HOST_PUBLIC_KEY_SHA256 and CURLOPT_SSH_KNOWNHOSTS. Conversely, the libcurl runtime successfully honors CURLOPT_DEFAULT_PROTOCOL and establishes the connection via SFTP/SCP as specified. Because the tool layer skipped the security configuration, these SSH host verification options are silently omitted, causing curl to connect to an unverified SSH remote host without throwing an error.

Impacted Vendors

H
haxx 1

Reference Links

https://curl.se/docs/CVE-2026-12064.html https://curl.se/docs/CVE-2026-12064.json https://hackerone.com/reports/3797526
CVSS v3.1
Source Entity 134c704f-9b21-4f2e-91b3-4a467353bcc0
Severity HIGH
7.5
Attack Vector
NETWORK
Complexity
LOW
Privileges
N/A
Interaction
NONE
Confidentiality
N/A
Integrity
N/A
Availability
N/A
Scope
UNCHANGED
RAW VECTOR CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Associated Attack Patterns (CAPEC)

Total: Patterns

CVE-2026-12064 Exploits & PoCs (Proof Of Concept)

No public PoCs found in our database for this CVE.

MODIFIED

Vulnerability data updated via NVD.

MODIFIED

Vulnerability data updated via NVD.

MODIFIED

Vulnerability data updated via NVD.

MODIFIED

Vulnerability data updated via NVD.

Attack Vector Matrix

Access Vector NETWORK
Complexity LOW
Privileges N/A
Interaction NONE
CVSS Vector String CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Affected Stack

No specific products linked.