Detections
Analytics
Security Updates for Microsoft Exchange Server (July 2026)
high Nessus Plugin ID 326858
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 a security update. It is, therefore, affected by multiple vulnerabilities as referenced in the July, 2026 security bulletin.- Improper neutralization of input during web page generation ('cross-site scripting') in Microsoft Exchange Server allows an unauthorized attacker to perform spoofing over a network. (CVE-2026-55008)
- Incorrect authorization in Microsoft Exchange Online allows an authorized attacker to elevate privileges over a network. (CVE-2026-54998)
- Heap-based buffer overflow in Microsoft Exchange Server allows an authorized attacker to execute code over a network. (CVE-2026-55005)
- Insufficient granularity of access control in Microsoft Exchange Server allows an authorized attacker to elevate privileges locally. (CVE-2026-55006)
- Deserialization of untrusted data in Microsoft Exchange Server allows an authorized attacker to elevate privileges locally. (CVE-2026-55009)
Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.
Solution
Microsoft has released the following security updates to address this issue:-KB5103213
-KB5103214
-KB5103215
Plugin Details
Severity: High
ID: 326858
File Name: smb_nt_ms26_jul_exchange.nasl
Version: 1.1
Type: Local
Agent: windows
Family: Windows : Microsoft Bulletins
Published: 7/14/2026
Updated: 7/14/2026
Supported Sensors: Nessus Agent, Nessus
Risk Information
VPR
Risk Factor: Medium
Score: 5
Percentile: 94.12
CVSS v2
Risk Factor: Critical
Base Score: 10
Temporal Score: 7.8
Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:C
CVSS Score Source: CVE-2026-55008
CVSS v3
Risk Factor: High
Base Score: 8.8
Temporal Score: 7.9
Vector: CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Temporal Vector: CVSS:3.0/E:P/RL:O/RC:C
CVSS Score Source: CVE-2026-54998
Vulnerability Information
CPE: cpe:/a:microsoft:exchange_server:2016, cpe:/a:microsoft:exchange_server:2019
Required KB Items: SMB/MS_Bulletin_Checks/Possible
Exploit Available: true
Exploit Ease: Exploits are available
Patch Publication Date: 7/14/2026
Vulnerability Publication Date: 7/2/2026
Reference Information
CVE: CVE-2026-54998, CVE-2026-55005, CVE-2026-55006, CVE-2026-55008, CVE-2026-55009