Detections
Analytics

Security Updates for Microsoft Excel Products C2R (June 2026)

high Nessus Plugin ID 320865

Synopsis

The Microsoft Excel Products are affected by multiple vulnerabilities.

Description

The Microsoft Excel Products are missing security updates. It is, therefore, affected by multiple vulnerabilities:

 - Integer underflow (wrap or wraparound) in Microsoft Office Excel allows an unauthorized attacker to execute code locally. (CVE-2026-44817, CVE-2026-44818, CVE-2026-44820, CVE-2026-44823, CVE-2026-45469)

 - Out-of-bounds read in Microsoft Office Excel allows an unauthorized attacker to disclose information over a network. (CVE-2026-44822, CVE-2026-45455)

 - Protection mechanism failure in Microsoft Office Excel allows an unauthorized attacker to bypass a security feature locally. (CVE-2026-45459)

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 patches to address these issues.

For Office 365, Office 2016 C2R, or Office 2019, 2021 or 2024, ensure automatic updates are enabled or open any office app and manually perform an update.

See Also

http://www.nessus.org/u?5931548c

Plugin Details

Severity: High

ID: 320865

File Name: smb_nt_ms26_jun_excel_c2r.nasl

Version: 1.1

Type: Local

Agent: windows

Family: Windows

Published: 6/12/2026

Updated: 6/12/2026

Supported Sensors: Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: High

Score: 7.4

CVSS v2

Risk Factor: High

Base Score: 8.5

Temporal Score: 6.3

Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:P/A:N

CVSS Score Source: CVE-2026-44822

CVSS v3

Risk Factor: High

Base Score: 8.2

Temporal Score: 7.1

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

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

CVSS Score Source: CVE-2026-44822

Vulnerability Information

CPE: cpe:/a:microsoft:excel

Required KB Items: SMB/MS_Bulletin_Checks/Possible

Exploit Ease: No known exploits are available

Patch Publication Date: 6/10/2026

Vulnerability Publication Date: 6/10/2026

Reference Information

CVE: CVE-2026-44817, CVE-2026-44818, CVE-2026-44820, CVE-2026-44822, CVE-2026-44823, CVE-2026-45455, CVE-2026-45459, CVE-2026-45469

IAVA: 2026-A-0570, 2026-A-0571