PT-2021-2734 · Microsoft · Exchange Server

Published 2021-04-13 · Updated 2026-03-17 · CVE-2021-28480

Positive Technologies (AI Summary)

CVSS v2.0

10

Critical

Base vector

AV:N/AC:L/Au:N/C:C/I:C/A:C

Name of the Vulnerable Software and Affected Versions Microsoft Exchange Server (affected versions not specified)

Description A flaw exists in Microsoft Exchange Server related to incorrect code generation management. Successful exploitation could allow a remote attacker to execute arbitrary code. Multiple reports indicate this is a remote code execution issue. The vulnerability involves a pre-authentication Server-Side Request Forgery (SSRF) and Access Control List (ACL) bypass, referred to as 'ProxyNotFound'.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Exploit

Code Injection

Weakness Enumeration

CWE-94

Related Identifiers

BDU:2021-02268

CVE-2021-28480

Affected Products

Exchange Server

References · 19

• 🔥 https://github.com/ZephrFish/CVE-2021-28480_HoneyPoC3 · Exploit
• 🔥 https://github.com/ZephrFish/ExchangeRCE-CVE-2021-28480 · Exploit
• http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-28480 · Security Note
• https://bdu.fstec.ru/vul/2021-02268 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2021-28480 · Security Note
• https://safe-surf.ru/specialists/bulletins-nkcki/663873 · Security Note
• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-28480 · Vendor Advisory
• https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2021-28480 · Vendor Advisory
• https://osv.dev/vulnerability/CVE-2021-28480 · Vendor Advisory
• https://t.me/cvenotify/13199 · Telegram Post
• https://t.me/cvenotify/13196 · Telegram Post
• https://t.me/cybersecuritytechnologies/3159 · Telegram Post
• https://t.me/cvenotify/13197 · Telegram Post
• https://t.me/ckure/7596 · Telegram Post
• https://twitter.com/pdnuclei_bot/status/2023744265298604173 · Twitter Post