CVE-2026-55090

MEDIUMPre-NVD 5.35.3—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 5.3 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.4%, top 65% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, secondary
5.3EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 5.3Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

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 v3
5.3
EG Score
5.3(medium)
EG Risk
39(Track)
EG Risk 39/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity53% × 45%
Exploitation0% × 40%
Automatability100% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
35%
KEV
Not listed

Published

August 17, 2026

Last Modified

September 9, 2026

Advisory Details (4)

Auto-updated Aug 19, 2026
Patch available. Sources: github, github_pr, github_commit, github_release.
github_release Patch Available

v3.3.0

Patch available: ether/etherpad v3.3.0

https://github.com/ether/etherpad/releases/tag/v3.3.0
github_commit Patch Available

commit 86c56cf827dd (ether/etherpad)

Patch available: ether/etherpad v3.3.0 (contains commit 86c56cf827dd)

https://github.com/ether/etherpad/commit/86c56cf827dd6e5ff1b6cd3760f87adc47f58bb1
github_pr Patch Available

Escape exported data attributes and warn on default/placeholder credentials

Patch available: ether/etherpad v3.3.0 (PR #7905 merged 2026-06-07)

https://github.com/ether/etherpad/pull/7905
github Patch Available

Stored XSS in HTML export via unescaped attribute-pool values · Advisory · ether/etherpad · GitHub

https://github.com/ether/etherpad/security/advisories/GHSA-2jp7-wwpg-3p9w

Vendor Advisories for CVE-2026-55090(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Affected Packages

(1 across 1 ecosystem)
npm(1)
PackageVulnerable rangeFixed inDependents
ep_etherpad-lite—3.3.0—

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 13× in last 7d / 52× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-09-19 04:59 UTCEG score recompute
  2. 2026-09-18 19:28 UTCEPSS rescore
  3. 2026-09-18 06:47 UTCEG score recompute
  4. 2026-09-17 19:31 UTCEPSS rescore
  5. 2026-09-17 08:36 UTCEG score recompute
  6. 2026-09-16 14:08 UTCEPSS rescore
  7. 2026-09-16 10:16 UTCEG score recompute
  8. 2026-09-16 05:15 UTCEPSS rescore
  9. 2026-09-15 12:04 UTCEG score recompute
  10. 2026-09-15 03:11 UTCEPSS rescore
  11. 2026-09-14 13:51 UTCEG score recompute
  12. 2026-09-13 16:47 UTCEPSS rescore
  13. 2026-09-12 17:25 UTCEG score recompute
  14. 2026-09-11 19:13 UTCEG score recompute
  15. 2026-09-11 14:53 UTCEPSS rescore
  16. 2026-09-10 20:50 UTCEG score recompute
  17. 2026-09-10 09:35 UTCEPSS rescore
  18. 2026-09-09 03:39 UTCEG score recompute
  19. 2026-09-08 22:01 UTCEPSS rescore
  20. 2026-09-07 16:11 UTCEG score recompute
  21. 2026-09-07 16:01 UTCEPSS rescore
  22. 2026-09-06 15:30 UTCEG score recompute
  23. 2026-09-06 13:47 UTCEPSS rescore
  24. 2026-09-05 17:18 UTCEG score recompute
  25. 2026-09-04 19:04 UTCEG score recompute
Show 31 more
  1. 2026-09-04 05:06 UTCEPSS rescore
  2. 2026-09-02 22:10 UTCEG score recompute
  3. 2026-09-02 14:12 UTCEPSS rescore
  4. 2026-09-01 22:26 UTCEG score recompute
  5. 2026-09-01 13:54 UTCEPSS rescore
  6. 2026-09-01 04:40 UTCEPSS rescore
  7. 2026-08-31 01:54 UTCEG score recompute
  8. 2026-08-30 19:17 UTCEPSS rescore
  9. 2026-08-30 03:42 UTCEG score recompute
  10. 2026-08-30 01:22 UTCEPSS rescore
  11. 2026-08-29 05:30 UTCEG score recompute
  12. 2026-08-28 21:41 UTCEPSS rescore
  13. 2026-08-27 23:39 UTCEG score recompute
  14. 2026-08-27 14:25 UTCEPSS rescore
  15. 2026-08-27 01:23 UTCEG score recompute
  16. 2026-08-26 14:46 UTCEPSS rescore
  17. 2026-08-26 03:12 UTCEG score recompute
  18. 2026-08-25 13:49 UTCEPSS rescore
  19. 2026-08-25 04:55 UTCEG score recompute
  20. 2026-08-23 08:32 UTCEG score recompute
  21. 2026-08-23 00:19 UTCEPSS rescore
  22. 2026-08-22 10:21 UTCEG score recompute
  23. 2026-08-21 23:49 UTCEPSS rescore
  24. 2026-08-21 12:09 UTCEG score recompute
  25. 2026-08-20 22:55 UTCEPSS rescore
  26. 2026-08-20 13:57 UTCEG score recompute
  27. 2026-08-20 12:42 UTCEG score recompute
  28. 2026-08-19 20:23 UTCEG score recompute
  29. 2026-08-19 19:43 UTCEG score recompute▲ 5.30
  30. 2026-08-19 19:42 UTCMITRE cvelistV5CVSS v3 → 5.3 · CVSS v4 → 5.3 · severity → MEDIUM
  31. 2026-08-17 17:54 UTCEG score recompute

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-55090?
CVE-2026-55090 is a medium vulnerability published on August 17, 2026. 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…
When was CVE-2026-55090 disclosed?
CVE-2026-55090 was first published in the National Vulnerability Database on August 17, 2026, with the most recent update on September 9, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-55090 actively exploited?
CVE-2026-55090 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 64.7% of all scored CVEs.
What is the CVSS score of CVE-2026-55090?
CVE-2026-55090 has a CVSS v3 base score of 5.3 (NVD).
How do I remediate CVE-2026-55090?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-55090, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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