CVE-2021-26855 is a critical Server-Side Request Forgery (SSRF) vulnerability affecting Microsoft Exchange Server, allowing unauthenticated remote code execution. With a CVSS score of 9.8, it presents a severe risk due to its network-based attack vector, low attack complexity, and high impact on confidentiality, integrity, and availability. This vulnerability is actively exploited in the wild, notably by ransomware campaigns, and has extensive public exploit code available, including Metasploit modules and Nuclei templates, leading to significant community discussion and media coverage.
| Vendor | Product | Version(s) | CPE |
|---|---|---|---|
2013CPE matchmatch criteria | cpe:2.3:a:microsoft:exchange_server:2013:cumulative_update_21:*:*:*:*:*:* | ||
2013CPE matchmatch criteria | cpe:2.3:a:microsoft:exchange_server:2013:cumulative_update_22:*:*:*:*:*:* | ||
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_10:*:*:*:*:*:* | ||
2016CPE matchmatch criteria | cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_11:*:*:*:*:*:* |
CVSS version used by this source: 3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
The average CVE in this peer group has 0.0 Twitter, 0.1 Reddit, 0.3 Bluesky, 0.3 Mastodon, and 2.4 GitHub mentions.
The average CVE in this peer group has 0.3 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.