CVE-2025-27399

Mastodon's domain blocks & rationales ignore user approval when visibility set as "users"

Published Feb 27, 2025 CVSS 3.1 · 5.3 Medium EPSS < 1% KEV · Not listed
Description
Mastodon is a self-hosted, federated microblogging platform. In versions prior to 4.1.23, 4.2.16, and 4.3.4, when the visibility for domain blocks/reasons is set to "users" (localized English string: "To logged-in users"), users that are not yet approved can view the block reasons. Instance admins that do not want their domain blocks to be public are impacted. Versions 4.1.23, 4.2.16, and 4.3.4 fix the issue.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
EUVD EUVD EUVD-2025-5447 Mastodon is a self-hosted, federated microblogging platform. In versions prior to 4.1.23, 4.2.16, and 4.3.4, when the visibility for domain blocks/reasons is set to "users" (localized English string: "To logged-in users"), users that are not yet approved can view the block reasons. Instance admins that do not want their domain blocks to be public are impacted. Versions 4.1.23, 4.2.16, and 4.3.4 fix the issue.
History
Type Values Removed Values Added
First Time appeared Joinmastodon
Joinmastodon mastodon
CPEs cpe:2.3:a:joinmastodon:mastodon:*:*:*:*:*:*:*:*
Vendors & Products Joinmastodon
Joinmastodon mastodon
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description Mastodon is a self-hosted, federated microblogging platform. In versions prior to 4.1.23, 4.2.16, and 4.3.4, when the visibility for domain blocks/reasons is set to "users" (localized English string: "To logged-in users"), users that are not yet approved can view the block reasons. Instance admins that do not want their domain blocks to be public are impacted. Versions 4.1.23, 4.2.16, and 4.3.4 fix the issue.
Title Mastodon's domain blocks & rationales ignore user approval when visibility set as "users"
Weaknesses CWE-200
CWE-285
References
Metrics cvssV3_1

{'score': 5.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Feb 27, 2025, 5:59 PM
Reserved
Feb 24, 2025, 3:51 PM
Status
Analyzed
Published
Feb 27, 2025, 6:15 PM
Modified
Jun 17, 2026, 9:03 AM