CVE-2025-10966: curl — Exploit & Fix

Description

curl's code for managing SSH connections when SFTP was done using the wolfSSH powered backend was flawed and missed host verification mechanisms. This prevents curl from detecting MITM attackers and more.

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CVSS v3.1 Score

4.3

MEDIUM

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

Affected Products

Vendor	Product	Versions
haxx	curl	7.69.0 — 8.17.0

References

Advisories & Patches

https://curl.se/docs/CVE-2025-10966.html https://curl.se/docs/CVE-2025-10966.json http://www.openwall.com/lists/oss-security/2025/11/05/2

Exploits

https://hackerone.com/reports/3355218

Frequently Asked Questions

What is CVE-2025-10966? +

curl's code for managing SSH connections when SFTP was done using the wolfSSH powered backend was flawed and missed host verification mechanisms. This prevents curl from detecting MITM attackers and more. It has a CVSS v3.1 base score of 4.3 (MEDIUM).

How severe is CVE-2025-10966? +

CVE-2025-10966 has a CVSS v3.1 score of 4.3 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2025-10966? +

CVE-2025-10966 affects products from haxx, specifically: curl. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-10966? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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CVE-2025-10966