CVE-2026-53950

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

HIGH

7.5

CVSS Score

Published: June 24, 2026 at 06:04 PM UTC

Updated: October 25, 2026 at 10:10 PM UTC

1 product affected across 1 vendorGhost

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Severity

HIGH7.5

Exploit prediction

EPSS 0.4%

SSVC

No known exploit

Description

@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

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Ghost · Tryghostnpm

90%

v < 3.1.0

Affected range stops below 3.1.0, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

References (1)

x_refsource_CONFIRM

Source: cverecord

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

SSVC — Action Prioritization

SSVCNo known exploitNot automatableTotal impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

7.5HIGHGitHub_M

Attack Vector: NETWORK
Complexity: HIGH
Privileges: NONE
User Interaction: REQUIRED
Scope: UNCHANGED
Confidentiality: HIGH
Integrity: HIGH
Availability: HIGH

Vector?

Quick Info

StatusDEFERRED

CWE

CWE-79

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