CVE-2025-67500 (GCVE-0-2025-67500)

Vulnerability from cvelistv5 – Published: 2025-12-09 23:44 – Updated: 2026-01-08 15:18
VLAI
Title
Mastodon Error Handling Discrepancy Enables Private Status Existence Enumeration
Summary
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.
Severity
3.7 (Low)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-12-10 15:42 UTC
CWE
  • CWE-204 - Observable Response Discrepancy
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7637 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
mastodon mastodon Affected: < 4.2.28
Affected: >= 4.3.0-beta.1, < 4.3.15
Affected: >= 4.4.0-beta.1, < 4.4.10
Affected: >= 4.5.0-beta.1, < 4.5.3
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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