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CVE-2026-45459

Microsoft Excel Security Feature Bypass Vulnerability

No known exploitation. EPSS puts it in the 31st percentile. Fixed versions are out.

CVSS 3.13.3LowEPSS percentile31st0.4% chance in 30 daysCISA KEVNot listedNo confirmed exploitation
No public exploit knownFix5 products2 fixed builds listed below
Check it yourself

OpenVAS · 1 check

e.g. OID 1.3.6.1.4.1.25623.1.3.1.2026.06.09.0

Run the check

Published Updated Sources: CVE.org, NVD, BDU

NVD CVE.org

What to do

Find your product and version, then upgrade to the build on the right.

  • Microsoft 365 Apps for EnterpriseAffected: ≥ 16.0.1, < https://aka.ms/OfficeSecurityReleasesUpgrade to: https://aka.ms/OfficeSecurityReleasesStated by: CVE record
  • Microsoft Office 365 for MacAffected: ≥ 1.0.0, < 16.110.26061317Upgrade to: 16.110.26061317Stated by: CVE record
  • Microsoft Office LTSC 2024Affected: ≥ 16.0.0, < https://aka.ms/OfficeSecurityReleasesUpgrade to: https://aka.ms/OfficeSecurityReleasesStated by: CVE record
  • Microsoft Office LTSC for Mac 2021Affected: ≥ 16.0.1, < 16.110.26061317Upgrade to: 16.110.26061317Stated by: CVE record
  • Microsoft Office LTSC for Mac 2024Affected: ≥ 16.0.0, < 16.110.26061317Upgrade to: 16.110.26061317Stated by: CVE record

Versions as the sources state them. Full version matrix after sign-in

Check it yourselfA free OpenVAS check exists for this CVE. Run it against your hosts.Is your organisation exposed?Request an assessment to establish which checks fit your systems.

What it is

From the CVE record

Protection mechanism failure in Microsoft Office Excel allows an unauthorized attacker to bypass a security feature locally.

In plain language

No plain-language summary for this CVE yet.

Exploitation

Where each signal puts this CVE on the scale from published to confirmed exploited.

EPSS31st
CISA KEV

Not in the catalog. CISA has not confirmed exploitation.

Public exploits

No public exploit or proof of concept found in the sources we track.

EPSS

0.4% chance of exploitation activity in the next 30 days, which ranks it in the 31st percentile of scored CVEs.

Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.

Lifecycle

7 events over 44 days, from the signal feeds we watch.

  1. Patch availablerecord updated
  2. OpenVAS check added
  3. Patch availablerecord updated
  4. Publishedweakness classified

Affected products

And 5 more affected products. See all after sign-in

Technical detail

CVSS 3.1 vector

Open in the CVSS calculator

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

Scored 3.3 by NVD.

How it is reached

  • Attack Vector LocalRequires local access to the vulnerable system (e.g. local login, malicious file)
  • Attack Complexity LowNo special conditions — the attack can be reliably reproduced
  • Privileges Required NoneNo authentication required — anyone can exploit this
  • User Interaction RequiredA user must click a link, open a file, or perform some action

Scope

  • Scope UnchangedImpact is limited to the vulnerable component itself

Impact if exploited

  • Confidentiality LowSome restricted information is disclosed, but limited in scope
  • Integrity NoneNo integrity impact
  • Availability NoneNo availability impact

Weaknesses

Sources

References in the record

In the news

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