Medium Cross-site scripting

CVE-2026-19943 — Gutenverse <= 4.0.2 - Authenticated (Contributor+) Stored Cross-Site Scripting via 'titleTag' Block Attribute

The Gutenverse – WordPress Blocks, Page Builder & Site Editor plugin for WordPress is vulnerable to Stored Cross-Site Scripting via 'titleTag' Block Attribute in all versions up to, and including, 4.0.2 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. The malicious titleTag value survives wp_kses_post on save because it is stored inside a block-comment delimiter and the live HTML is only synthesized at render time by do_blocks(), meaning the payload also fires in administrator and editor sessions during post preview.

Published Aug 25, 2026 · Updated Oct 13, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: Wordfence

Low

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.

How the score was calculated

EPSS 0.2% (30-day exploitation probability)+1
Technical severity (medium)+3

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation

Not confirmed

Not in CISA KEV — an absence of record, not proof it is unexploited.

EPSS FIRST

0.2%

ahead of 9% of scored CVEs · Oct 15, 2026

Affects

Jegstudio

Gutenverse – WordPress Blocks, Page Builder & Site Editor

CVSS base

6.4

Medium · 2 source(s)

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation

None

none · proof-of-concept · active

Automatable

can an attacker script the kill-chain steps

Technical impact

Partial

partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

Identify exposed assets running the affected vendor/product/version combinations (Jegstudio Gutenverse – WordPress Blocks, Page Builder & Site Editor).
No fix documented in the sources: reduce exposure and monitor the vendor advisory.
Search available logs for exploit probes matching the vulnerability class (cross-site scripting), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

Vendor	Product	Versions	Status	Source
Jegstudio	Gutenverse – WordPress Blocks, Page Builder & Site Editor	≤ 4.0.2	Vulnerable	CVE Program (cve.org) e CISA ADP

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector

Network

Attack complexity

Low

Privileges required

Low

User interaction

None

Scope

Changed

Confidentiality

Low

Integrity

Low

Availability

None

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

Score	Version	Severity	Expl.	Impact	Scored by
6.4	CVSS 3.1	Medium	3.1	2.7	security@wordfence.com via NIST National Vulnerability Database
6.4	CVSS 3.1	Medium	—	—	Wordfence via CVE Program (cve.org) e CISA ADP

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N (score shown at the top: security@wordfence.com)

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-79 · Cross-site Scripting (XSS)

Other CVEs with this weakness →

EPSS over time FIRST

Oct 13, 2026 → Oct 15, 2026 · 3 reading(s) · max 0.20%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
Monitor CSP violation reports and script payloads in reflected parameters.

web/proxy/WAF logsnetwork IDS/IPSapplication logs

Timeline

What happened to this CVE, newest first.

2026
Affected products added · jegstudio/gutenverse – wordpress blocks, page builder & site editor
Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
SSVC assessment updated
Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
Record published
Oct 13, 2026
CVSS changed · 6.4
Oct 13, 2026 · NIST National Vulnerability Database
Source status changed · → Deferred
Oct 13, 2026 · NIST National Vulnerability Database
Record created in this database
Oct 13, 2026 · NIST National Vulnerability Database
CVE published
Aug 25, 2026 · Wordfence

Source activity

Repeated readings are counted rather than listed.

1× Official description updated · Oct 13, 2026 – Oct 13, 2026

References

6 on the record

plugins.trac.wordpress.org/browser/gutenverse/tags/4.0.0/includes/block/class-chart.php
NIST National Vulnerability Database
plugins.trac.wordpress.org/browser/gutenverse/tags/4.0.2/includes/block/class-chart.php
NIST National Vulnerability Database
plugins.trac.wordpress.org/browser/gutenverse/tags/4.0.0/includes/block/class-chart.php
NIST National Vulnerability Database
www.wordfence.com/threat-intel/vulnerabilities/id/b7eb4cac-cf16-438e-81cc-516646e77cdc
NIST National Vulnerability Database
plugins.trac.wordpress.org/changeset
NIST National Vulnerability Database
plugins.trac.wordpress.org/browser/gutenverse/tags/4.0.2/includes/block/class-chart.php
NIST National Vulnerability Database

Elsewhere on this site

Jegstudio
every CVE for this vendor

Cross-site scripting
same class

CWE-79
other pages naming this weakness

Related CVEs (same products)

Medium CVE-2026-92746 Gutenverse <= 4.0.8 - Authenticated (Contributor+) Stored Cross-Site Scripting via Post Comment Block 'suffixMain' Attribute 20d
Medium CVE-2026-3002 Gutenverse <= 4.0.2 - Authenticated (Contributor+) Stored Cross-Site Scripting via Multiple Blocks Aug 26, 2026
Medium CVE-2026-12399 Gutenverse <= 3.8.0 - Authenticated (Editor+) Stored Cross-Site Scripting via 'fonts[].font.font.value' Parameter Jun 27, 2026
Medium CVE-2026-3001 Gutenverse <= 3.4.6 - Reflected Cross-Site Scripting via 's' Parameter May 27, 2026

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

No fixed version, patch or mitigation documented.
No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-19943 is "Gutenverse <= 4.0.2 - Authenticated (Contributor+) Stored Cross-Site Scripting via 'titleTag' Block Attribute", rated Medium. It affects Gutenverse – WordPress Blocks, Page Builder & Site Editor (Jegstudio); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 6.4 describes technical severity. EPSS 0.20% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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