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.
Advisories
No advisories yet.
Fixes
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
References
History
Thu, 25 Jun 2026 14:30:00 +0000
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ssvc
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Thu, 25 Jun 2026 13:30:00 +0000
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Joinmastodon
Joinmastodon mastodon |
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| Vendors & Products |
Joinmastodon
Joinmastodon mastodon |
Wed, 24 Jun 2026 20:00:00 +0000
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| 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. | |
| Title | Mastodon: Removal of integrity-protected JSON entries from signed activities | |
| Weaknesses | CWE-354 | |
| References |
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| Metrics |
cvssV3_1
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Projects
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Status: PUBLISHED
Assigner: GitHub_M
Published:
Updated: 2026-06-25T13:26:34.764Z
Reserved: 2026-05-20T17:44:09.587Z
Link: CVE-2026-48028
Updated: 2026-06-25T13:26:30.447Z
No data.
No data.
OpenCVE Enrichment
Updated: 2026-06-25T13:15:03Z
Weaknesses