cve.bz

CVE-2026-48028

6.5 mediumEPSS 0.2%

Medium (6.5). EPSS 0.2% chance of exploitation in the next 30 days.

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.

Severity

CVSS 3.1

6.5 medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L
EPSS
0.2% chance of exploitation in the next 30 days; higher than 7% of CVEs (scores of 2026-10-31)
CWE
CWE-354
Published
Modified
Record from
the NVD, synced

References

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