Is CVE-2026-42558 in the CISA KEV catalog?

No. CVE-2026-42558 is not currently on the CISA Known Exploited Vulnerabilities list.

What is the CVSS severity of CVE-2026-42558?

CVE-2026-42558 has a CVSS v3 base score of 7.6 (HIGH).

What is the EPSS score for CVE-2026-42558?

CVE-2026-42558 has an EPSS score of 0.11% (2th percentile), estimating the probability of exploitation in the next 30 days.

How do I fix or mitigate CVE-2026-42558?

No published fix for CVE-2026-42558 has been found yet. Check the linked vendor advisories for guidance as it becomes available.

CVE & CISA-KEV Catalog

CVE-2026-42558

HIGH

7.6

CVSS v3

NVD

Description

Xibo is an open source digital signage platform with a web content management system and Windows display player software. Prior to 4.4.2, a vulnerability chain consisting of Stored XSS and Iframe Sandbox escape in the Xibo CMS allows users with DataSet permissions to use the Data Connector functionality to craft messages which escape the sandbox and facilitate XSS. Exploitation of the vulnerability is possible on behalf of an authorized user who has both of the following privileges, which are not granted to non-admins as standard: Include "Add DataSet" button to allow for additional DataSets to be created independently to Layouts Users should upgrade to version 4.4.2 which fixes this issue. Upgrading to a fixed version is necessary to remediate. Users unable to upgrade should revoke such privileges from users they do not trust.

CWE-79Cross-Site Scripting (XSS)CWE-116 CWE-346

How to fix

No published remediation has been found for this vulnerability's affected products yet.

Mitigation guidance may be in the linked vendor advisories in the References section below.

CVSS v3 Vector

Exploitability

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredLow

User InteractionRequired

ScopeChanged

Impact

ConfidentialityHigh

IntegrityLow

AvailabilityNone

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:L/A:N

Exploit Intelligence

0.11%probability of exploitation in 30 days

2ndpercentile

Low risk: more likely to be exploited than 2% of all known CVEs.

References

Other references1

github.com

Embed a live status badge for CVE-2026-42558

Markdown

[![CVE-2026-42558](https://tridentstack.com/cve/badge/CVE-2026-42558.svg)](https://tridentstack.com/cve/CVE-2026-42558)

HTML

<a href="https://tridentstack.com/cve/CVE-2026-42558"><img src="https://tridentstack.com/cve/badge/CVE-2026-42558.svg" alt="CVE-2026-42558"></a>

Find and fix vulnerabilities across your fleet

TridentStack Control continuously scans your Windows, macOS, and Linux fleet for known vulnerabilities, prioritizes them by severity and active exploitation, and patches them automatically.

Start free

This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-06-11.