CVE-2021-33766 is a critical information disclosure vulnerability affecting Microsoft Exchange Server, allowing unauthorized access to sensitive data. With a CVSS score of 7.5 (High), it presents a low-complexity, unauthenticated network attack vector that can lead to complete confidentiality compromise. This vulnerability is actively exploited in the wild, as confirmed by its presence in CISA's KEV catalog, and has garnered significant community attention and media coverage, including reports of its use in state-sponsored operations. While no Metasploit or ExploitDB modules exist, Nuclei templates for an authentication bypass related to this vulnerability are available.
| Vendor | Product | Version(s) | CPE |
|---|---|---|---|
2013CPE matchmatch criteria | cpe:2.3:a:microsoft:exchange_server:2013:cumulative_update_23:*:*:*:*:*:* | ||
2016CPE matchmatch criteria | cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_19:*:*:*:*:*:* | ||
2016CPE matchmatch criteria | cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_20:*:*:*:*:*:* | ||
2019CPE matchmatch criteria | cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_8:*:*:*:*:*:* | ||
2019CPE matchmatch criteria | cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_9:*:*:*:*:*:* |
CVSS version used by this source: 3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
The average CVE in this peer group has 0.0 Twitter, 0.0 Reddit, 0.1 Bluesky, 0.1 Mastodon, and 0.4 GitHub mentions.
The average CVE in this peer group has 0.1 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.