---
id: "CVE-2026-107146"
kind: "vulnerability"
aliases: ["CVE-2026-107146"]
title: "Roundcube 2FA plugin: failed verification leaves session alive for attacker"
severity: "medium"
cvss: 6.3
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["package", "roundcube", "self-hosted", "two-factor-auth", "webmail"]
not_affected_if: ["no-2fa-enabled", "plugin-not-installed"]
published_at: "2026-10-27T10:16:54+00:00"
first_seen_at: "2026-10-27T10:31:02+00:00"
updated_at: "2026-10-27T10:31:58+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-107146", "first_seen_at": "2026-10-27T10:31:02+00:00"}]
---

# Roundcube 2FA plugin: failed verification leaves session alive for attacker

The twofactor_gauthenticator plugin for Roundcube does not destroy the server-side session after a failed second-factor check, so the session stays valid. An attacker who already has the user's password can keep that session and keep guessing the second-factor code.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check whether the installed Roundcube has the twofactor_gauthenticator plugin enabled in `config/config.inc.php` under `plugins`
- Compare the plugin source against upstream commit `4640889`; the sources do not name a fixed release version

## Fix

- Update the twofactor_gauthenticator plugin to a release that includes commit `4640889`; the sources do not name the version
- unknown for any other configuration change

## Timeline

- 2026-10-27T10:31:02+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-107146

## From the sources

The twofactor_gauthenticator plugin for Roundcube is vulnerable to session persistence after failed 2FA verification. Due to the lack of server-side session destruction, an attacker can ignore the logout redirect and keep the session alive. This may allow an attacker who obtains user's password to e.g. brute force the second-factor code.




This issue was fixed in commit 4640889.

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