CVE-2026-109392

Pimcore through 2026.3.1 contains a stored cross-site scripting vulnerability that allows authenticated backend users to inject scripts by storing unescaped URLs in ExternalImage fields. Attackers with data object edit permission can store attribute-breaking payloads that execute JavaScript in the admin origin when other users open version preview or diff views.

CVSS 4.0

5.1CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N

CVSS 3.1

5.4CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

EPSS

0.2% chance of exploitation in the next 30 days; higher than 6% of CVEs (scores of 2026-10-25)

CWE

CWE-79

Published

2026-10-12

Modified

2026-10-13

Record from

the NVD, synced 2026-10-19

References

• https://github.com/pimcore/admin-ui-classic-bundle/blob/2.3/templates/admin/data_object/data_object/preview_version.html.twig#L198
• https://github.com/pimcore/pimcore
• https://github.com/pimcore/pimcore/blob/v2026.3.1/models/DataObject/ClassDefinition/Data/ExternalImage.php#L169-L203
• https://hackmd.io/@1ExmmukzRMWN7B4gQ4W-4Q/rJCbgCKjMe
• https://www.vulncheck.com/advisories/pimcore-through-2026.3.1-stored-xss-via-externalimage-field-version-preview

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