---
id: CVE-2026-117470
title: WebAuthn assertion replay permits second-factor bypass in Psono Server
summary: >-
  Psono Server CE & EE versions 3.1.0 through 7.2.3 did not consume a stored
  WebAuthn challenge after assertion verification. An unauthenticated remote
  attacker who possessed the user's password and one captured valid WebAuthn
  assertion co…
severity: medium
cvss: 6.5
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:H/A:N'
cvssSource: cna
cwe:
  - CWE-294
vendor: esaqa GmbH
product: Psono
affected:
  - Psono >= 3.1.0 < 7.2.4
published: '2026-10-27'
updated: '2026-10-27'
sourceUpdated: '2026-10-27T05:53:41.709Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-117470'
references:
  - url: >-
      https://gitlab.com/esaqa/esaqa/security-advisories/-/blob/master/advisories/CVE-2026-117470.md
    label: Vendor security advisory for CVE-2026-117470
  - url: >-
      https://gitlab.com/esaqa/psono/psono-server/-/blob/v7.2.3/psono/restapi/serializers/webauthn_verify.py
  - url: >-
      https://gitlab.com/esaqa/psono/psono-server/-/commit/9c9a7f1701535df63370340dcc80210737dc495d
  - url: 'https://gitlab.com/esaqa/psono/psono-server/-/releases/v7.2.4'
  - url: 'https://gitlab.com/esaqa/psono/psono-server'
tags:
  - cve.org
epss: 0.00408
epssPercentile: 0.34915
ingestedAt: '2026-10-27T16:11:59.222Z'
---

## Overview

Psono Server CE & EE versions 3.1.0 through 7.2.3 did not consume a stored WebAuthn challenge after assertion verification. An unauthenticated remote attacker who possessed the user's password and one captured valid WebAuthn assertion could replay that assertion with separate login tokens while the stored challenge remained unchanged, bypassing the WebAuthn second factor. The attack required capture of a valid assertion and did not itself disclose plaintext secrets.

## Affected

- `Psono >= 3.1.0 < 7.2.4`

## Remediation

Upgrade to Psono Server 7.2.4 or later.