CVE-2025-67500: Mastodon Error Handling Discrepancy Enables Private Status Existence Enumeration
Mastodon is a free, open-source social network server based on ActivityPub. Versions 4.2.27 and prior, 4.3.0-beta.1 through 4.3.14, 4.4.0-beta.1 through 4.4.9, 4.5.0-beta.1 through 4.5.2 have discrepancies in error handling which allow checking whether a given status exists by sending a request with a non-English Accept-Language header. Using this behavior, an attacker who knows the identifier of a particular status they are not allowed to see can confirm whether this status exists or not. This cannot be used to learn the contents of the status or any other property besides its existence. This issue is fixed in versions 4.2.28, 4.3.15, 4.4.10 and 4.5.3.
Affected Software
Remediation
Event History
Frequently Asked Questions
What is the severity of CVE-2025-67500?
CVE-2025-67500 has a medium severity rating due to its potential impact on privacy and information disclosure.
How do I fix CVE-2025-67500?
To fix CVE-2025-67500, upgrade Mastodon to version 4.2.28 or later, or apply the recommended patches provided in the security advisory.
Which versions are affected by CVE-2025-67500?
CVE-2025-67500 affects Mastodon versions up to 4.2.27 and several beta releases between 4.3.0-beta.1 and 4.5.2.
What type of vulnerability is CVE-2025-67500?
CVE-2025-67500 is a vulnerability related to discrepancies in error handling, allowing potential information leakage.
Is CVE-2025-67500 a critical vulnerability?
CVE-2025-67500 is not classified as critical, but it still poses a risk if not addressed.