CVE-2026-55086
On a host with a shared world-writable temporary directory, a local unprivileged attacker who predicts a filename can precreate a symbolic link to a file writable by the Etherpad process.
Does this matter?
Lower severity and a low EPSS score (0.14%). Track it; it rarely justifies an emergency change on its own.
Description
Etherpad is a real-time collaborative editor. Prior to 3.1.0, src/node/handler/ImportHandler.ts and src/node/handler/ExportHandler.ts derive temporary filenames from Math.random() and place them in os.tmpdir(). On a host with a shared world-writable temporary directory, a local unprivileged attacker who predicts a filename can precreate a symbolic link to a file writable by the Etherpad process. Subsequent import or export operations can follow the link through fs.writeFile, fs.rename, or document-conversion output and overwrite the target with partially attacker-controlled content. This issue is fixed in version 3.1.0.
- CVSS 3.1
- 4.2 MEDIUMCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:N
- EPSS
- 0.14% probability · 3th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-59, CWE-377
- Source
- security-advisories@github.com
EPSS 0.1% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://github.com/ether/etherpad/commit/8c6104c5d5daf41f0d454acc04d42dffa0e0d996
- https://github.com/ether/etherpad/pull/7784
- https://github.com/ether/etherpad/releases/tag/v3.1.0
- https://github.com/ether/etherpad/security/advisories/GHSA-2jwf-f4xq-f24h
- https://github.com/ether/etherpad/security/advisories/GHSA-2jwf-f4xq-f24h
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.