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.
References5
Metrics
- CVSS 3.1
-
4.2
MEDIUM
Score source: CNA
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:N - EPSS — exploit probability
- 0% percentile: 3 · as of 10 November 2026
- CWE
- CWE-59CWE-377
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