Is CVE-2026-2021 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-2021 being exploited in the wild.

How severe is CVE-2026-2021?

Medium severity, with a CVSS score of 6.4, published 18 June 2026.

Which products and versions are affected?

Tribulant Software Slideshow Gallery LITE up to, and including, 1.8.5.

Is there a fix for CVE-2026-2021?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

How is CVE-2026-2021 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-2021?

Check whether you run Tribulant Software Slideshow Gallery LITE at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-2021: Tribulant Slideshow Gallery LITE Stored XSS in alwaysauto shortcode

CVE-2026-2021 · Severity: medium · CVSS 6.4 · Published 2026-06-18

The Slideshow Gallery LITE plugin for WordPress, which is used to create image galleries on websites, contains a security flaw that allows users with contributor-level access to inject malicious scripts into pages. When other users or administrators visit these affected pages, the hidden scripts will execute in their browsers. This could lead to unauthorized actions being performed on behalf of the victim or the theft of sensitive session information.

Vendors: Tribulant Software.

Quick answers

Is CVE-2026-2021 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-2021 being exploited in the wild.
How severe is CVE-2026-2021?: Medium severity, with a CVSS score of 6.4, published 18 June 2026.
Which products and versions are affected?: Tribulant Software Slideshow Gallery LITE up to, and including, 1.8.5.
Is there a fix for CVE-2026-2021?: No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-2021 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-2021?: Check whether you run Tribulant Software Slideshow Gallery LITE at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

The Slideshow Gallery LITE plugin for WordPress is vulnerable to Stored Cross-Site Scripting (XSS) due to insufficient input sanitization and output escaping on the 'alwaysauto' shortcode attribute. This vulnerability exists in all versions up to and including 1.8.5. An authenticated attacker with Contributor-level permissions or higher can exploit this by embedding malicious JavaScript within a shortcode on a post or page. Because the input is stored in the database and rendered without proper neutralization (CWE-79), the script will execute in the context of any user's browser who views the affected content. A patch appears to be available in the plugin's trunk/latest changeset.

Affected products

Tribulant Slideshow Gallery LITE up to, and including, 1.8.5

Timeline

2026-06-18: disclosed
2026-06-18: advisory

References

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