CVE-2026-53950: @tryghost/activitypub is Ghost’s social/federation client app. Prior to 3.1.0, the ActivityPub client in Ghost was vulnerable to JavaScript injection on posts…

PriorityP341high7.5CVSS 3.1

AVNACHPRNUIRSUCHIHAH

EPSS

0.35%

26.6th percentile

@tryghost/activitypub is Ghost’s social/federation client app. Prior to 3.1.0, the ActivityPub client in Ghost was vulnerable to JavaScript injection on posts shared by a maliciously customised ActivityPub server. This vulnerability is fixed in 3.1.0.

Affected

2 ranges

Vendor	Product	Version range	Fixed in
tryghost	activitypub	>= 0 < 3.1.0	3.1.0
tryghost	ghost	< 3.1.0	3.1.0

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