Vulnerability identifier: #VU19077

Vulnerability risk: Medium

CVSSv3.1: 6.4 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N/E:U/RL:W/RC:C]

CVE-ID: N/A

CWE-ID: CWE-79

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Microsoft Exchange Server
Server applications / Mail servers

Vendor: Microsoft

Description

The disclosed vulnerability allows a remote attacker to perform cross-site scripting (XSS) attacks.

The vulnerability exists due to insufficient sanitization of user-supplied data passed via SVG images. A remote attacker can send a specially crafted email message that contains a malicious SVG image and and execute arbitrary HTML and script code in user's browser in context of Outlook on the web (formerly known as Outlook Web App) website.

Successful exploitation of this vulnerability may allow a remote attacker to steal potentially sensitive information, change appearance of the web page, perform phishing and drive-by-download attacks.

Mitigation

Vulnerable software versions

Microsoft Exchange Server: 2010, 2013 RTM 15.00.0516.032 - 2013 Cumulative Update 23 15.00.1497.002, 2016 RTM 15.01.0225.042 - 2016 Cumulative Update 13 15.01.1779.002, 2019 RTM 15.02.0221.012 - 2019 Cumulative Update 2 15.02.0397.003

---

External links
http://portal.msrc.microsoft.com/en-US/security-guidance/advisory/ADV190021

---

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

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