CVE-2026-9547

CVE Enrichment

CVSS: 7.4 HIGH
EPSS: 0.36%
EPSS Percentile: 29.87%
CISA KEV: Not listed

Description

When a libcurl-based application performs transfers via `SCP://` or `SFTP://` and utilizes the `CURLOPT_SSH_KEYFUNCTION` callback, it may silently accept an untrusted server. This vulnerability occurs when a server presents a host key type that does not match the specific key type already recorded for that host in the `known_hosts` file. Instead of rejecting the mismatch, the callback mechanism fails to properly enforce the restriction, allowing the connection to succeed without warning and risking a potential man-in-the-middle attack.

Technical Details

CVSS Version: 3.1
CNA / NVD Source: 2499f714-1537-4658-8207-48ae4bb9eae9
Published: 03-Jul-2026 14:16
Last Modified: 15-Sep-2026 14:16
EPSS Date: 2026-10-29
CWE: CWE-297

CVSS Vector


            CVSS:3.1                            AV:N /
                            AC:H /
                            PR:N /
                            UI:N /
                            S:U /
                            C:H /
                            I:H /
                            A:N

Affected Products / Versions

haxx / curl
Version / affected range: * · from (inclusive) 7.69.0 · before (exclusive) 8.21.0
cpe:2.3:a:haxx:curl:*:*:*:*:*:*:*:*

References

Last enrichment sync: 30-Oct-2026 12:01
Sources: NVD · FIRST EPSS · CISA KEV
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Reported Context (1)

The other identified flaws include credential confusion (CVE-2026-8926), double-free (CVE-2026-8925), use-after-free (CVE-2026-9080 and CVE-2026-10536), and improper host validation (CVE-2026-9547). curl Update Patches 18 Vulnerabilities, Including 25-Year-Old Potential Authentication Bypass

CVE (5)

Vendors (2)

Products (3)

Note: Related entities, including threat actors, malware, CVEs, MITRE ATT&CK techniques, vendors, products, tools, countries, and industries, are shown when they appear in the same reporting. Their presence does not necessarily mean they were targeted, compromised, vulnerable, responsible for the activity, or directly involved in the incident.