Description
Etherpad is a real-time collaborative editor. From 2.6.0 until 3.1.0, Etherpad's src/node/hooks/express/tokenTransfer.ts uses POST /tokenTransfer to store an author token for transfer between browsers and exposes it through GET /tokenTransfer/{uuid}. Although the record includes createdAt, the transfer has no expiration check, is not removed after successful redemption, and is returned by res.send(tokenData), including the raw author token. An unauthenticated attacker who obtains a transfer UUID can repeatedly redeem it, receive fresh author cookies, read the cleartext token, and impersonate the originating author for pad read and write operations. This issue is fixed in version 3.1.0.
References4
Metrics
- CVSS 3.1
-
6.8
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N - EPSS — exploit probability
- 0% percentile: 38 · as of 10 November 2026
- CWE
- CWE-200CWE-294
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