Description
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.
Published: 2026-08-19
Score: 5.3 Medium
EPSS: n/a
KEV: No
Impact: n/a
Action: n/a
AI Analysis

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Remediation

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Tracking

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Advisories
Source ID Title
Github GHSA Github GHSA GHSA-2jp7-wwpg-3p9w Etherpad has stored XSS in HTML export via unescaped attribute-pool values
History

Wed, 19 Aug 2026 19:45:00 +0000

Type Values Removed Values Added
Description 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.
Title Etherpad: Stored XSS in HTML export via unescaped attribute-pool values
Weaknesses CWE-79
References
Metrics cvssV4_0

{'score': 5.3, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N'}

Subscriptions

No data.

cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-08-19T19:32:17.607Z

Reserved: 2026-06-16T14:41:54.578Z

Link: CVE-2026-55090

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-08-19T20:17:18.233

Modified: 2026-08-19T20:17:18.233

Link: CVE-2026-55090

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.

Weaknesses
  • CWE-79

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