Ghost vulnerable to remote code execution in locale setting change
Impact
A vulnerability in an upstream library means an authenticated attacker can abuse locale input to execute arbitrary commands from a file that has previously been uploaded using the file upload functionality in the post editor.
Patches
Fixed in 5.2.3, all 5.x sites should update as soon as possible. Fixed in 4.48.2, all 4.x sites should update as soon as possible.
Workarounds
Patched versions of Ghost add validation to the locale input to prevent execution of arbitrary files. Updating Ghost is the quickest complete solution.
As a workaround, if for any reason you cannot update your Ghost instance, you can block the POST /ghost/api/admin/settings/ endpoint, which will also disable updating settings for your site.
For more information
If you have any questions or comments about this advisory:
- Email us at security@ghost.org
Credits
- devx00 - https://twitter.com/devx00
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A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.
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