CVE-2026-53950
@tryghost/activitypub: XSS in Ghost's ActivityPub client
@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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- None
- User interaction
- Required
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
@tryghost/activitypub: XSS in Ghost's ActivityPub client
@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.
- Record
CVE-2026-53950- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-79
- Updated
- 2026-11-02
EUVDEUVD-2026-39019
@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.
- Record
EUVD-2026-39019- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-xpp7-93x6-v29m
XSS in Ghost's ActivityPub client
Impact
The ActivityPub client in Ghost was vulnerable to JavaScript injection on posts shared by a maliciously customised ActivityPub server.
Vulnerable Versions
This vulnerability is present in the @tryghost/activitypub package up to v3.0.8. All prior versions are also affected.
Patches
@tryghost/activitypub v3.1.0 contains a fix for this issue and is also automatically fetched by Ghost.
References
Ghost thanks Brad Geesaman, Ghost Security for disclosing this vulnerability responsibly.
For more information
If you have any questions or comments about this advisory, email Ghost at [email protected].
- Record
GHSA-xpp7-93x6-v29m- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-79
- Updated
- 2026-11-02
NVD
@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.
- Record
CVE-2026-53950- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-79
- Updated
- 2026-11-02
OSV
@tryghost/activitypub: XSS in Ghost's ActivityPub client
@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.
- Record
CVE-2026-53950- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-79
- Updated
- 2026-11-02
OSVGHSA-xpp7-93x6-v29m
XSS in Ghost's ActivityPub client
Impact
The ActivityPub client in Ghost was vulnerable to JavaScript injection on posts shared by a maliciously customised ActivityPub server.
Vulnerable Versions
This vulnerability is present in the @tryghost/activitypub package up to v3.0.8. All prior versions are also affected.
Patches
@tryghost/activitypub v3.1.0 contains a fix for this issue and is also automatically fetched by Ghost.
References
Ghost thanks Brad Geesaman, Ghost Security for disclosing this vulnerability responsibly.
For more information
If you have any questions or comments about this advisory, email Ghost at [email protected].
- Record
GHSA-xpp7-93x6-v29m- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-79
- Updated
- 2026-11-02
OSVBIT-ghost-2026-53950 No score
@tryghost/activitypub: XSS in Ghost's ActivityPub client
@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.
- Record
BIT-ghost-2026-53950- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
@tryghost/activitypubnpm |
before 3.1.0 | 3.1.0 |
ghostBitnami |
before 3.1.0 | 3.1.0 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-53950 is a high vulnerability (CVSS 7.5) in Tryghost Ghost, published June 24, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.35%, the 29th percentile. Fixed in @tryghost/activitypub 3.1.0.