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: 0.5% (43rd percentile of EPSS-scored CVEs). 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: 0.5%CVSS: 5.3Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

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
5.3MEDIUMmedium confidence
EG Risk
39
EG Risk 39/100CISA SSVC

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%
Exploitation1% × 40%
Automatability100% × 15%
CISA SSVC: Track at low or medium mission impact; Attend at high (mission-essential systems).
Action: A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.
EPSS PROB
0.5%
EPSS %ILE
43rd
KEV
Not listed

CISA SSVCTrack at low or medium mission impact; Attend at high (mission-essential systems).

A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.

Exploitation none (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Mission impact is CISA's Mission & Well-being decision point, and only you can judge it: high means the affected system is essential to your organisation's mission, or its compromise could cause irreversible harm to people. CISA's decision table

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 rangeFix by version rangeDependents
ep_etherpad-lite—
  • every version up to 3.3.0: fixed in 3.3.0
—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 12× in last 7d / 49× 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. 2026-10-04 23:22 UTCEPSS rescore
  2. 2026-10-03 17:48 UTCEG score recompute
  3. 2026-10-03 14:26 UTCEPSS rescore
  4. 2026-10-02 17:56 UTCEPSS rescore
  5. 2026-10-02 06:57 UTCEG score recompute
  6. 2026-10-01 19:50 UTCEPSS rescore
  7. 2026-10-01 08:11 UTCEG score recompute
  8. 2026-09-30 15:03 UTCEPSS rescore
  9. 2026-09-30 10:00 UTCEG score recompute
  10. 2026-09-29 15:22 UTCEPSS rescore
  11. 2026-09-29 04:29 UTCEG score recompute
  12. 2026-09-28 13:51 UTCEPSS rescore
  13. 2026-09-28 06:17 UTCEG score recompute
  14. 2026-09-27 13:48 UTCEPSS rescore
  15. 2026-09-27 08:06 UTCEG score recompute
  16. 2026-09-26 15:59 UTCEPSS rescore
  17. 2026-09-25 02:02 UTCEG score recompute
  18. 2026-09-24 14:04 UTCEPSS rescore
  19. 2026-09-23 20:27 UTCEG score recompute
  20. 2026-09-23 17:54 UTCEPSS rescore
  21. 2026-09-22 22:13 UTCEG score recompute
  22. 2026-09-22 00:01 UTCEG score recompute
  23. 2026-09-21 01:49 UTCEG score recompute
  24. 2026-09-20 20:16 UTCEPSS rescore
  25. 2026-09-20 03:11 UTCEG score recompute
Show 56 more
  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
  26. 2026-09-04 05:06 UTCEPSS rescore
  27. 2026-09-02 22:10 UTCEG score recompute
  28. 2026-09-02 14:12 UTCEPSS rescore
  29. 2026-09-01 22:26 UTCEG score recompute
  30. 2026-09-01 13:54 UTCEPSS rescore
  31. 2026-09-01 04:40 UTCEPSS rescore
  32. 2026-08-31 01:54 UTCEG score recompute
  33. 2026-08-30 19:17 UTCEPSS rescore
  34. 2026-08-30 03:42 UTCEG score recompute
  35. 2026-08-30 01:22 UTCEPSS rescore
  36. 2026-08-29 05:30 UTCEG score recompute
  37. 2026-08-28 21:41 UTCEPSS rescore
  38. 2026-08-27 23:39 UTCEG score recompute
  39. 2026-08-27 14:25 UTCEPSS rescore
  40. 2026-08-27 01:23 UTCEG score recompute
  41. 2026-08-26 14:46 UTCEPSS rescore
  42. 2026-08-26 03:12 UTCEG score recompute
  43. 2026-08-25 13:49 UTCEPSS rescore
  44. 2026-08-25 04:55 UTCEG score recompute
  45. 2026-08-23 08:32 UTCEG score recompute
  46. 2026-08-23 00:19 UTCEPSS rescore
  47. 2026-08-22 10:21 UTCEG score recompute
  48. 2026-08-21 23:49 UTCEPSS rescore
  49. 2026-08-21 12:09 UTCEG score recompute
  50. 2026-08-20 22:55 UTCEPSS rescore
  51. 2026-08-20 13:57 UTCEG score recompute
  52. 2026-08-20 12:42 UTCEG score recompute
  53. 2026-08-19 20:23 UTCEG score recompute
  54. 2026-08-19 19:43 UTCEG score recompute▲ 5.30
  55. 2026-08-19 19:42 UTCMITRE cvelistV5CVSS v3 → 5.3 · CVSS v4 → 5.3 · severity → MEDIUM
  56. 2026-08-17 17:54 UTCEG score recompute

Related CVEs(same product + 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 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 0.5% probability of exploitation in the next 30 days (43rd percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-55090?
CVE-2026-55090 has a CVSS base score of 5.3 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-55090?
A fix for CVE-2026-55090 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-55090 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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