---
id: CVE-2026-104733
title: >-
  User Impersonation in ProcessOnes XMMP Server ejabberd <= 26.04 allows an
  attacker to impersonate arbitrary users via unvalidated authzid parameter in
  SASL-PLAIN mechanism.
summary: >-
  User Impersonation in ProcessOnes XMMP Server ejabberd <= 26.04 allows an
  attacker to impersonate arbitrary users via unvalidated authzid parameter in
  SASL-PLAIN mechanism.
severity: high
cvss: 7.4
cvssVector: 'CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:H/SC:H/SI:H/SA:H/E:P'
vendor: ProcessOne
product: ejabberd
affected:
  - ejabberd <= 26.04
published: '2026-10-02'
updated: '2026-10-02'
sourceUpdated: '2026-10-02T13:17:45.010'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-104733'
references:
  - url: 'https://github.com/processone/ejabberd/releases#release-26.07'
    label: vulnerability@ncsc.ch
  - url: 'https://www.nsideattacklogic.de/advisories/NSIDE-SA-2026-004/'
    label: vulnerability@ncsc.ch
tags:
  - nvd
  - cve.org
cvssSource: cna
ingestedAt: '2026-10-02T13:19:14.157Z'
---

## Overview

User Impersonation in ProcessOnes XMMP Server ejabberd <= 26.04 allows an attacker to impersonate arbitrary users via unvalidated authzid parameter in SASL-PLAIN mechanism.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.