CVE-2026-53950 PUBLISHED

@tryghost/activitypub: XSS in Ghost's ActivityPub client

Assigner: GitHub_M
Reserved: 11.06.2026 Published: 24.06.2026 Updated: 24.06.2026

@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.

Metrics

CVSS 3.1

CVSS Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
CVSS Score: 7.5

Attack Vector	Network	Scope	Unchanged
Attack Complexity	High	Confidentiality Impact	High
Privileges Required	None	Integrity Impact	High
User Interaction	Required	Availability Impact	High

CVSS 3.1

Product Status

Vendor	TryGhost
Product	Ghost
Versions	Version < 3.1.0 is affected

References

https://github.com/TryGhost/Ghost/security/advisories/GHSA-xpp7-93x6-v29m

Problem Types

CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') CWE