Security Updates for Exchange (May 2021)

high Nessus Plugin ID 149393

Synopsis

The Microsoft Exchange Server installed on the remote host is affected by multiple vulnerabilities.

Description

The Microsoft Exchange Server installed on the remote host is missing security updates. It is, therefore, affected by multiple vulnerabilities:
- A security feature bypass vulnerability exists. An attacker can exploit this and bypass the security feature and perform unauthorized actions compromising the integrity of the system/application.
(CVE-2021-31207)
- A remote code execution vulnerability. An attacker can exploit this to bypass authentication and execute unauthorized arbitrary commands. (CVE-2021-31195, CVE-2021-31198)
- A session spoofing vulnerability exists. An attacker can exploit this to perform actions with the privileges of another user. (CVE-2021-31209)

Solution

Microsoft has released KB5003435 to address this issue.

See Also

http://www.nessus.org/u?812d3faa

Plugin Details

Severity: High

ID: 149393

File Name: smb_nt_ms21_may_exchange.nasl

Version: 1.11

Type: local

Agent: windows

Published: 5/11/2021

Updated: 5/10/2022

Risk Information

VPR

Risk Factor: Critical

Score: 9.5

CVSS v2

Risk Factor: Medium

Base Score: 6.8

Temporal Score: 5.9

Vector: AV:N/AC:M/Au:N/C:P/I:P/A:P

Temporal Vector: E:H/RL:OF/RC:C

CVSS Score Source: CVE-2021-31198

CVSS v3

Risk Factor: High

Base Score: 8.8

Temporal Score: 8.4

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Temporal Vector: E:H/RL:O/RC:C

CVSS Score Source: CVE-2021-31195

Vulnerability Information

CPE: cpe:/a:microsoft:exchange_server

Required KB Items: SMB/MS_Bulletin_Checks/Possible

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 5/11/2021

Vulnerability Publication Date: 5/11/2021

CISA Known Exploited Dates: 11/17/2021

Exploitable With

Metasploit (Microsoft Exchange ProxyShell RCE)

Reference Information

CVE: CVE-2021-31195, CVE-2021-31198, CVE-2021-31207, CVE-2021-31209

MSKB: 5003435

MSFT: MS21-5003435

IAVA: 2021-A-0221-S