---
id: CVE-2026-62911
title: >-
  Authentication bypass by capture-replay in Microsoft Exchange Server allows an
  authorized attacker to elevate privileges over a network.
summary: >-
  Authentication bypass by capture-replay in Microsoft Exchange Server allows an
  authorized attacker to elevate privileges over a network.
severity: high
cvss: 8
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H'
cwe:
  - CWE-294
vendor: microsoft
product: exchange_server
affected:
  - exchange_server = 2016
  - exchange_server = 2019
  - exchange_server_subscription_edition < 15.02.2562.046
patched:
  - exchange_server_subscription_edition 15.02.2562.046
published: '2026-08-11'
updated: '2026-10-14'
sourceUpdated: '2026-10-14T22:10:00.210'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-62911'
references:
  - url: 'https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-62911'
    label: secure@microsoft.com
  - url: 'https://github.com/hypnguyen1209/CVE-2026-62911'
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
tags:
  - nvd
  - cve.org
  - exploit-available
exploitAvailable: true
ssvc:
  exploitation: poc
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-08-06T00:00:00+00:00'
epss: 0.00694
epssPercentile: 0.52742
exploits:
  github: 3
  githubRepos:
    - 'https://github.com/hypnguyen1209/CVE-2026-62911'
    - 'https://github.com/ZeroDayEvil/CVE-2026-62911'
    - 'https://github.com/fahise/cve-2026-62911'
  checkedAt: '2026-10-27T19:06:41.649Z'
ingestedAt: '2026-09-08T18:07:34.890Z'
---

## Overview

Authentication bypass by capture-replay in Microsoft Exchange Server allows an authorized attacker to elevate privileges over a network.

## Affected

- `exchange_server = 2016`
- `exchange_server = 2019`
- `exchange_server_subscription_edition < 15.02.2562.046`

## Remediation

Upgrade past the affected range:

- `exchange_server_subscription_edition 15.02.2562.046`