CVE-2021-34473

2021-07-1400:00:00

attackerkb.com

139

9.8 High

CVSS3

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

NONE

User Interaction

NONE

Scope

UNCHANGED

Confidentiality Impact

HIGH

Integrity Impact

HIGH

Availability Impact

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

10 High

CVSS2

Access Vector

NETWORK

Access Complexity

LOW

Authentication

NONE

Confidentiality Impact

COMPLETE

Integrity Impact

COMPLETE

Availability Impact

COMPLETE

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

0.973 High

EPSS

Percentile

99.9%

Microsoft Exchange Server Remote Code Execution Vulnerability This CVE ID is unique from CVE-2021-31196, CVE-2021-31206.

Recent assessments:

gwillcox-r7 at July 14, 2021 5:15pm UTC reported:

From <https://blog.talosintelligence.com/2021/07/microsoft-patch-tuesday-for-july-2021.html> there was a note that this vulnerability seems to have been used in some Exchange Server APT attacks detailed at <https://blog.talosintelligence.com/2021/03/hafnium-update.html> however it wasn’t disclosed that this vulnerability was patched despite being patched back in April 2021. Since this was under active exploitation it is recommended to patch this vulnerability if you haven’t applied April 2021’s patch updates already.

Successful exploitation will result in RCE on affected Exchange Servers, and requires no prior user privileges, so patch this soon!

Assessed Attacker Value: 5
Assessed Attacker Value: 5Assessed Attacker Value: 3