---
id: "CVE-2026-114732"
kind: "vulnerability"
aliases: ["CVE-2026-114732"]
title: "Roundcube Webmail: alias login can resolve to a user on another IMAP host"
severity: "medium"
cvss: 6.8
epss: 0.00358
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["email", "multi-host", "package", "roundcube", "self-hosted"]
not_affected_if: ["patched-version", "single-imap-host"]
published_at: "2026-10-22T03:16:38+00:00"
first_seen_at: "2026-10-23T21:57:30+00:00"
updated_at: "2026-10-25T03:42:52+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-114732", "first_seen_at": "2026-10-23T21:57:30+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2026-114732", "first_seen_at": "2026-10-24T07:15:51+00:00"}]
---

# Roundcube Webmail: alias login can resolve to a user on another IMAP host

Roundcube Webmail before 1.6.20 and 1.7.x before 1.7.5 looks up alias logins without matching the IMAP host, so a login can resolve to a user account on a different IMAP host. An attacker may be able to log in as a user from another host in a multi-host installation.

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

## How to check

- Check the installed version with `bin/roundcube` or the Roundcube about page; versions below `1.6.20` on the 1.6 line, or below `1.7.5` on the 1.7 line, are in scope
- Confirm whether the installation serves several IMAP hosts (multi-host `default_host` or `imap_host` arrays in config)

## Fix

- Upgrade Roundcube Webmail to `1.6.20` or later on the 1.6 line, or `1.7.5` or later on the 1.7 line
- Apply the upstream commit “Fix bug where an alias login wasn’t qualified by IMAP host” if an immediate upgrade is not possible

## Timeline

- 2026-10-23T21:57:30+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-114732
- 2026-10-24T07:15:51+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2026-114732

## From the sources

Roundcube Webmail before 1.6.20 and 1.7.x before 1.7.5 is affected by an improper authentication vulnerability in multi-host installations. When a user logs in with an alias address, rcube_user::query() matched the address against identity records without qualifying the lookup by IMAP host, so a login could be resolved to a user account belonging to a different IMAP host. Upstream fixed this in the commit “Fix bug where an alias login wasn’t qualified by IMAP host”.

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_