CVE-2026-55090

Etherpad is a real-time collaborative editor. Prior to 3.3.0, getHTMLFromAtext in src/node/utils/ExportHtml.ts interpolates values from the exportHtmlAdditionalTagsWithData plugin hook into span data attributes without HTML attribute escaping. A pad editor can place an attacker-controlled value into the attribute pool through moveOpsToNewPool and AttributePool.putAttrib. When a bundled plugin such as ep_font_color or ep_font_size registers the hook, opening the resulting HTML export causes the value to execute as stored cross-site scripting in the Etherpad origin. This issue is fixed in version 3.3.0.

CVSS

No CVSS.

References

Link	Resource
https://github.com/ether/etherpad/commit/86c56cf827dd6e5ff1b6cd3760f87adc47f58bb1
https://github.com/ether/etherpad/pull/7905
https://github.com/ether/etherpad/releases/tag/v3.3.0
https://github.com/ether/etherpad/security/advisories/GHSA-2jp7-wwpg-3p9w

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-19 20:17

Updated : 2026-09-09 21:15

NVD link : CVE-2026-55090

Mitre link : CVE-2026-55090

CVE.ORG link : CVE-2026-55090

JSON object : View

Products Affected

No product.

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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