BIT-mastodon-2026-48028: Mastodon: Removal of integrity-protected JSON entries from signed activities
Mastodon is a free, open-source social network server based on ActivityPub. Prior to 4.5.10, 4.4.17, and 4.3.23, Mastodon's normalization of incoming activities signed with Linked-Data Signatures does not sufficiently protect the activities from a certain class of spoofing, allowing threat actors to remove JSON entries from valid signed activities from a third-party actor. This vulnerability is fixed in 4.5.10, 4.4.17, and 4.3.23.
BIT-mastodon-2026-48028: Mastodon: Removal of integrity-protected JSON entries from signed activities
Description
Mastodon is a free, open-source social network server based on ActivityPub. Prior to 4.5.10, 4.4.17, and 4.3.23, Mastodon's normalization of incoming activities signed with Linked-Data Signatures does not sufficiently protect the activities from a certain class of spoofing, allowing threat actors to remove JSON entries from valid signed activities from a third-party actor. This vulnerability is fixed in 4.5.10, 4.4.17, and 4.3.23.
Affected software
pkg:bitnami/mastodonRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- BIT-mastodon-2026-48028
- Osv Schema Version
- 1.6.2
- Aliases
- ["CVE-2026-48028"]
- Ecosystems
- ["Bitnami"]
- Database Specific Severity
- Medium
- Cvss Version
- null
Threat ID: 6a4c347427e9c79719603a98
Added to database: 07/06/2026, 23:04:20 UTC
Last updated: 07/06/2026, 23:04:20 UTC
Views: 1
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