Description
Microsoft Exchange Server Information Disclosure Vulnerability
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Microsoft | Microsoft Exchange Server 2013 Cumulative Update 23 | 15.00.0 – < 15.00.1497.015 | 15.00.1497.015 |
| Microsoft | Microsoft Exchange Server 2016 Cumulative Update 19 | 15.01.0 – < 15.01.2176.012 | 15.01.2176.012 |
| Microsoft | Microsoft Exchange Server 2016 Cumulative Update 20 | 15.01.0 – < 15.01.2242.008 | 15.01.2242.008 |
| Microsoft | Microsoft Exchange Server 2019 Cumulative Update 8 | 15.02.0 – < 15.02.0792.013 | 15.02.0792.013 |
| Microsoft | Microsoft Exchange Server 2019 Cumulative Update 9 | 15.02.0 – < 15.02.0858.010 | 15.02.0858.010 |
Public exploits
Exploit or proof-of-concept code for this vulnerability is publicly available, which lowers the bar for attackers. Treat it as a reason to patch sooner.
GitHub 2 repositories
-
bhdresh/CVE-2021-33766 ★ 45 · Aug 31, 2021
ProxyToken (CVE-2021-33766) : An Authentication Bypass in Microsoft Exchange Server POC exploit
-
demossl/CVE-2021-33766-ProxyToken ★ 10 · Sep 15, 2021
CVE-2021-33766-poc
Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.
Automated scanner template
A ready-made Nuclei template detects this vulnerability automatically. Vulnerabilities with public scanner templates are typically probed across the internet soon after the template appears — exposed systems should be patched first.
- Microsoft Exchange - Authentication Bypass http/cves/2021/CVE-2021-33766.yaml
Source: projectdiscovery/nuclei-templates (MIT) — updated daily. Only links are listed.
Advisories 2
- WID-SEC-2024-1897 Microsoft Exchange Server: Mehrere Schwachstellen BSI CERT-Bund (WID) · Aug 21, 2024
- MSRC-CVE-2021-33766 Microsoft Exchange Server Information Disclosure Vulnerability Microsoft Security Response Center · Jul 13, 2021
References
- Microsoft Exchange Server Information Disclosure Vulnerability vendor-advisory patch