Input validation error in Etherpad - #VU151603
Published: September 22, 2026
Vulnerability identifier: #VU151603
CSH Severity: Medium
CVSS v4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N]
CVE-ID: N/A
CWE-ID: CWE-20
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to create arbitrary pads.
The vulnerability exists due to improper input validation in API.appendChatMessage when appending chat messages to a specified pad. A remote attacker can invoke API.appendChatMessage for a nonexistent pad to create arbitrary pads.
Affected software
Etherpad
Remediation
Install security update from vendor's website.
Etherpad - update to 3.3.0