CVE-2026-55085
What it is
Etherpad is a real-time collaborative editor. Prior to 3.3.1, result.appendSpan in src/static/js/domline.ts interpolates the start attribute of a numbered list directly into an unquoted ol start attribute before assigning the generated markup to node.innerHTML. ImportEtherpad.setPadRaw in src/node/utils/ImportEtherpad.ts accepts attacker-controlled attribute-pool values from a crafted .etherpad import, including list:number1 and a malicious start value. Any user with write access to a pad can store markup that executes as cross-site scripting when another user opens the pad or /timeslider, including when an administrator views the pad. This issue is fixed in version 3.3.1.
At a glance
- Exploitability
- Can be exploited over the network without logging in, but needs a user to act. High risk of data exposure, data tampering.
- Exploit odds
- 0.5% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- ReservedThe CVE id was reserved by its CNA
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.5% in the next 30 days (EPSS).
- Severity: 9.6 CRITICAL (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.5% · EPSS, next 30 days
- Weakness
- CWE-79 · Cross-site scripting
- Record status
- Deferred
Attack profile CVSS 3.1 · 9.6
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Required
- Scope
- Changed
- Confidentiality
- High
- Integrity
- High
- Availability
- Low
Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:L
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2026-55085.md and follow it. Check whether this project is affected by CVE-2026-55085. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://github.com/ether/etherpad/commit/d828185efcac9abc2e46e6da1c171393500fa319
- https://github.com/ether/etherpad/pull/7937
- https://github.com/ether/etherpad/releases/tag/v3.3.1
- https://github.com/ether/etherpad/security/advisories/GHSA-f7h5-v9hm-548j
- https://github.com/ether/etherpad/security/advisories/GHSA-f7h5-v9hm-548j
References
- https://github.com/ether/etherpad/commit/d828185efcac9abc2e46e6da1c171393500fa319
- https://github.com/ether/etherpad/pull/7937
- https://github.com/ether/etherpad/releases/tag/v3.3.1
- https://github.com/ether/etherpad/security/advisories/GHSA-f7h5-v9hm-548j
- https://github.com/ether/etherpad/security/advisories/GHSA-f7h5-v9hm-548j