Reference page — cumulative record through Sunday, October 4, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.

CVE-2026-12064

CVE-2026-12064HIGH

curl curl — proto-default skips SSH verification

  AV  AC  PR  UI  S  C  I  A   CVSS    EPSS   %ile   KEV
   N   L   N   N  U  N  H  N    7.5   .0040   31.8     —

AFFECTED
  Product  Versions                                    Fixed
  curl     7.81.0 –                                    —
  curl     18270893abdb19f0ca170c118f8a2847dbd304be –  —
  curl     8.20.0 –                                    —

TIMELINE
  Jun 12  Reserved by curl
  Jul 3   EXPLOIT PUBLISHED — CVE-2026-12064 (curl). Public exploit reference added.
  Jul 3   Published (CNA: curl)
  Sep 15  EXPLOIT PUBLISHED — CVE-2026-12064 (curl). Public exploit reference added.

CWE-295, CWE-297 · CNA: curl · CVSS v3.1 · 3 references · NVD status: Modified

Description

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.

Lifecycle

Complete event history — 4 events, chronological
Date	Event	Detail
June 12, 2026	Reserved	Reserved by curl
July 3, 2026	EXPLOIT PUBLISHED	EXPLOIT PUBLISHED — CVE-2026-12064 (curl). Public exploit reference added.
July 3, 2026	Published	Published (CNA: curl)
September 15, 2026	EXPLOIT PUBLISHED	EXPLOIT PUBLISHED — CVE-2026-12064 (curl). Public exploit reference added.

Affected

Affected products and packages — 3 rows
Vendor	Product / Package	Ecosystem	Version introduced	Fixed
curl	curl	—	7.81.0	—
curl	curl	—	18270893abdb19f0ca170c118f8a2847dbd304be	—
curl	curl	—	8.20.0	—

Weaknesses

CWE-295 · CWE-297

References (3)

https://curl.se/docs/CVE-2026-12064.html [Patch, Vendor Advisory]
https://curl.se/docs/CVE-2026-12064.json [Vendor Advisory]
https://hackerone.com/reports/3797526 [Exploit, Issue Tracking, Third Party Advisory]

Authoritative record: CVE-2026-12064 at cve.org

Vendors: curl

Weaknesses: CWE-295 · CWE-297

About this page

This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-12064 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Sunday, October 4, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.