CVE-2026-9547

Publication date 24 June 2026

Last updated 26 June 2026


Ubuntu priority

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.

Why is this CVE low priority?

Upstream defined this as low severity

Learn more about Ubuntu priority

Status

Package Ubuntu Release Status
curl 26.04 LTS resolute
Vulnerable
25.10 questing
Vulnerable
24.04 LTS noble
Vulnerable
22.04 LTS jammy
Vulnerable
20.04 LTS focal
Not affected
18.04 LTS bionic
Not affected
16.04 LTS xenial
Not affected
14.04 LTS trusty
Not affected

Patch details

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Package Patch details
curl

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