CVE-2026-9547

Friday, July 03, 2026

N/A

Summary

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.

Affected Software

Vendor	Product	Version Range	Status
curl	curl	`8.20.0 <= 8.20.0`	affected
curl	curl	`8.19.0 <= 8.19.0`	affected
curl	curl	`8.18.0 <= 8.18.0`	affected
curl	curl	`8.17.0 <= 8.17.0`	affected
curl	curl	`8.16.0 <= 8.16.0`	affected
curl	curl	`8.15.0 <= 8.15.0`	affected
curl	curl	`8.14.1 <= 8.14.1`	affected
curl	curl	`8.14.0 <= 8.14.0`	affected
curl	curl	`8.13.0 <= 8.13.0`	affected
curl	curl	`8.12.1 <= 8.12.1`	affected
curl	curl	`8.12.0 <= 8.12.0`	affected
curl	curl	`8.11.1 <= 8.11.1`	affected
curl	curl	`8.11.0 <= 8.11.0`	affected
curl	curl	`8.10.1 <= 8.10.1`	affected
curl	curl	`8.10.0 <= 8.10.0`	affected
curl	curl	`8.9.1 <= 8.9.1`	affected
curl	curl	`8.9.0 <= 8.9.0`	affected
curl	curl	`8.8.0 <= 8.8.0`	affected
curl	curl	`8.7.1 <= 8.7.1`	affected
curl	curl	`8.7.0 <= 8.7.0`	affected
curl	curl	`8.6.0 <= 8.6.0`	affected
curl	curl	`8.5.0 <= 8.5.0`	affected
curl	curl	`8.4.0 <= 8.4.0`	affected
curl	curl	`8.3.0 <= 8.3.0`	affected
curl	curl	`8.2.1 <= 8.2.1`	affected
curl	curl	`8.2.0 <= 8.2.0`	affected
curl	curl	`8.1.2 <= 8.1.2`	affected
curl	curl	`8.1.1 <= 8.1.1`	affected
curl	curl	`8.1.0 <= 8.1.0`	affected
curl	curl	`8.0.1 <= 8.0.1`	affected
curl	curl	`8.0.0 <= 8.0.0`	affected
curl	curl	`7.88.1 <= 7.88.1`	affected
curl	curl	`7.88.0 <= 7.88.0`	affected
curl	curl	`7.87.0 <= 7.87.0`	affected
curl	curl	`7.86.0 <= 7.86.0`	affected
curl	curl	`7.85.0 <= 7.85.0`	affected
curl	curl	`7.84.0 <= 7.84.0`	affected
curl	curl	`7.83.1 <= 7.83.1`	affected
curl	curl	`7.83.0 <= 7.83.0`	affected
curl	curl	`7.82.0 <= 7.82.0`	affected
curl	curl	`7.81.0 <= 7.81.0`	affected
curl	curl	`7.80.0 <= 7.80.0`	affected
curl	curl	`7.79.1 <= 7.79.1`	affected
curl	curl	`7.79.0 <= 7.79.0`	affected
curl	curl	`7.78.0 <= 7.78.0`	affected
curl	curl	`7.77.0 <= 7.77.0`	affected
curl	curl	`7.76.1 <= 7.76.1`	affected
curl	curl	`7.76.0 <= 7.76.0`	affected
curl	curl	`7.75.0 <= 7.75.0`	affected
curl	curl	`7.74.0 <= 7.74.0`	affected
curl	curl	`7.73.0 <= 7.73.0`	affected
curl	curl	`7.72.0 <= 7.72.0`	affected
curl	curl	`7.71.1 <= 7.71.1`	affected
curl	curl	`7.71.0 <= 7.71.0`	affected
curl	curl	`7.70.0 <= 7.70.0`	affected
curl	curl	`7.69.1 <= 7.69.1`	affected
curl	curl	`7.69.0 <= 7.69.0`	affected

Weaknesses

CWE-297 Improper Validation of Certificate with Host Mismatch

References

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