CVE-2026-55086: ep_etherpad-lite · Import/export uses Math.random() for temp file paths; predictable paths on shared /tmp enable symlink-based file overwrite
Affects ep_etherpad-liteSource GCVE Database
Not known to be exploited · CVSS 4.2 Medium : upgrade to 3.1.0 when convenient.
Data as of 10 Nov 2026, 23:24 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 3% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 3.1.0
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:NExploitation evidence
t = 0 is the CVE’s publication on cve.org
Disclosed: evidence found.
CVE published 19 Aug 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: evidence found.
CISA SSVC: proof of concept public
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
Timeline
CVE ID reserved
by GitHub, Inc.
, 64 days before disclosure
CVE published
on cve.org
, t = 0
CISA SSVC assessment
proof of concept public
, 6 days after disclosure
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), CISA SSVC, the Metasploit, Exploit-DB and nuclei-templates index as of 11 Nov 2026.
What to do
Upgrade ep_etherpad-lite to 3.1.0.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| npmep_etherpad-lite | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Upgrade Etherpad-lite to version 3.1.0 or later, where this vulnerability is fixed. The fix removes the use of predictable Math.random() for temporary filenames, preventing symlink-based overwrites. No other mitigation is required if the upgrade is applied.
Description
Etherpad-lite versions prior to 3.1.0 use Math.random() to generate temporary filenames for import/export operations in a shared temporary directory. This allows a local unprivileged attacker to predict these filenames and create symbolic links that cause the Etherpad process to overwrite arbitrary files with attacker-controlled content. The vulnerability is fixed in version 3.1.0.