CVE Catalog

CVE-2025-62605

MediumCVSS 4.3
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.29%

20th percentile - higher than 20% of all known CVEs

Summary

Mastodon version 4.4 added support for verifiable quote posts with quote controls, but in versions prior to 4.4.8 and 4.5.0-beta.2 an attacker can bypass these controls. Since reblogs are internally treated as statuses, an attacker could reblog any post, then quote their reblog, technically quoting themselves but having the quote feature preview a post they were not authorized for. The issue is patched in versions 4.4.8 and 4.5.0-beta.2.

Risk Assessment

An attacker can bypass quote controls and expose previews of posts they are not authorized to, violating privacy expectations. The impact scope is limited but can lead to unauthorized content dissemination.

Recommendation

Update Mastodon to version 4.4.8 or 4.5.0-beta.2 (or later). Until updated, consider restricting the quote feature if possible.

Other vulnerabilities in Mastodon

See all
Original NVD description (English source)

Mastodon is a free, open-source social network server based on ActivityPub. In Mastodon version 4.4, support for verifiable quote posts with quote controls was added, but it is possible for an attacker to bypass these controls in Mastodon versions prior to 4.4.8 and 4.5.0-beta.2. Mastodon internally treats reblogs as statuses. Since they were not special-treated, an attacker could reblog any post, then quote their reblog, technically quoting themselves, but having the quote feature a preview of the post they did not get authorization for with all of the affordances that would be otherwise denied by the quote controls. This issue has been patched in versions 4.4.8 and 4.5.0-beta.2.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS