CVE-2026-9547 Affecting curl package, versions <8.21.0-r0


Severity

Recommended
low

Based on default assessment until relevant scores are available.

Threat Intelligence

EPSS
0.19% (9th percentile)

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  • Snyk IDSNYK-ALPINE324-CURL-17717707
  • published30 Jun 2026
  • disclosed3 Jul 2026

Introduced: 30 Jun 2026

NewCVE-2026-9547  (opens in a new tab)

How to fix?

Upgrade Alpine:3.24 curl to version 8.21.0-r0 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream curl package and not the curl package as distributed by Alpine. See How to fix? for Alpine:3.24 relevant fixed versions and status.

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.