CVE-2026-48028: medium-severity vulnerability in mastodon
Mastodon: Removal of integrity-protected JSON entries from signed activities
Published · Updated
13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 6.5epss 0.2%
exploitation probability
0.2%top 94% of all CVEs
observed exploitation
nono source reports it
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L
Affected products
mastodon · mastodonRelated CVEs — mastodon
In the same product, most dangerous first.
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