CVE-2026-53950

highpriority · track · 0EPSS 0.004 · 29 %ileEUUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

0.35% (29th) EPSS

CVSS 7.5 · high

Is it mine?

3 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · osv

EPSS · scored 2026-10-27

@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.

cvss

Technical severity, 0–10. One row per scoring source.

7.5

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.9–7.5

v3.17.5highCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:Hsecondary · ENISA EU

v3.17.5highCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:Hsecondary · security-advisories@github.comexploitability 1.6 · impact 5.9

v3.17.5highCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:Hsecondary · OSV

v3.16.9mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: no · Technical Impact: totalcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-79USprimaryCWE-79US

affected products (3)

Products and version ranges known to be affected.

TryGhost Ghost≤ < 3.1.0enisa_euvdEU
Bitnami ghost< 3.1.0osvUSpkg:bitnami/ghost
npm @tryghost/activitypub< 3.1.0osvUSpkg:npm/%40tryghost/activitypub

advisories (2)

Vendor and ecosystem advisories describing this.

GHSA-xpp7-93x6-v29mXSS in Ghost's ActivityPub client2026-08-04ghsa · osvUS
### 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 [security@ghost.org](mailto:security@ghost.org).
BIT-ghost-2026-53950@tryghost/activitypub: XSS in Ghost's ActivityPub client2026-06-30vendor · osvUS
@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.

also known as (5)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd osv NVD CVE.org MITRE

published 2026-06-24modified 2026-10-25

related (53,011)

Related entries.

ID	severity	EPSS	exploitable	published
CVE-2026-42897US	medium6.1OT critical	70.7% (99th)	KEV	2026-05-14
Improper neutralization of input during web page generation ('cross-site scripting') in Microsoft Exchange Server allows an unauthorized attacker to perform spoofing over a network…
CVE-2025-66376US	medium6.1OT critical	20.2% (97th)	KEV	2026-01-05
Zimbra Collaboration (ZCS) 10 before 10.0.18 and 10.1 before 10.1.13 allows Classic UI stored XSS via Cascading Style Sheets (CSS) @import directives in an HTML e-mail message.
CVE-2025-68461US	medium6.1OT critical	27.4% (98th)	KEV	2025-12-18
Roundcube Webmail before 1.5.12 and 1.6 before 1.6.12 is prone to a Cross-Site-Scripting (XSS) vulnerability via the animate tag in an SVG document.
CVE-2025-48700US	—OT critical	1.71% (77th)	KEV	2025-06-23
An issue was discovered in Zimbra Collaboration (ZCS) 8.8.15 and 9.0 and 10.0 and 10.1. A Cross-Site Scripting (XSS) vulnerability in the Zimbra Classic UI allows attackers to exec…
CVE-2025-27915US	—OT critical	4.06% (91st)	KEV	2025-03-12
An issue was discovered in Zimbra Collaboration (ZCS) 9.0 and 10.0 and 10.1. A stored cross-site scripting (XSS) vulnerability exists in the Classic Web Client due to insufficient…

+53006 more

references (3)

External citations — patches, advisories, analysis.

scry

Attackers weaponise vulnerabilities like this against internet-exposed services. See what is exposed on your perimeter with a free passive scan.

Free scan