Server-side request forgery in Microsoft Exchange server

1) Server-Side Request Forgery (SSRF)

EUVDB-ID: #VU82691

Risk: Medium

CVSSv3.1: 4.6 [CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N/E:U/RL:U/RC:C]

CVE-ID: N/A

CWE-ID: CWE-918 - Server-Side Request Forgery (SSRF)

Exploit availability: No

Description

The disclosed vulnerability allows a remote user to perform SSRF attacks.

The vulnerability exists due to insufficient validation of user-supplied input within CreateAttachmentFromUr(), DownloadDataFromOfficeMarketPlace(), and DownloadDataFromUri() methods. A remote user can send a specially crafted HTTP request and force the application to initiate requests to arbitrary resources.

Successful exploitation of this vulnerability may allow a remote attacker gain access to sensitive data, located in the local network or send malicious requests to other servers from the vulnerable system.

Mitigation

Cybersecurity Help is currently unaware of any official solution to address this vulnerability.

Vulnerable software versions

Microsoft Exchange Server: 2016 CU22 Nov22SU 15.01.2375.037 - 2019 RTM Mar21SU 15.02.0221.018

External links

http://www.zerodayinitiative.com/advisories/ZDI-23-1581/
http://www.zerodayinitiative.com/advisories/ZDI-23-1580/
http://www.zerodayinitiative.com/advisories/ZDI-23-1579/

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

How the attacker can exploit this vulnerability?

The attacker would have to send a specially crafted request to the affected application in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.