Microsoft Office Outlook Missing User Interaction for Potentially Unsafe Action
CVE-2026-124194 is a medium-severity missing user interaction for potentially unsafe action vulnerability in Microsoft 365 Apps for Enterprise from Microsoft, with a CVSS 3.1 base score of 6.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, but only if a user takes part, for example by opening a link or file. The record lists version https://aka.ms/OfficeSecurityReleases as the first without the flaw, so updating Microsoft 365 Apps for Enterprise to that release or later removes the exposure. CISA added it to the Known Exploited Vulnerabilities catalogue on November 10, 2026, which means attacks have been observed in the wild.
Attackers are already exploiting this vulnerability, according to CISA.
What to do
- Update Microsoft 365 Apps for Enterprise to https://aka.ms/OfficeSecurityReleases or a later version.
- Update Microsoft Office LTSC 2021 to 16.0.14334.21048 or a later version.
- Update Microsoft Office LTSC 2024 to 16.0.17932.21140 or a later version.
- CISA's required action: Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
- Read the advisory on msrc.microsoft.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
- Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Microsoft | Microsoft 365 Apps for Enterprise | 16.0.1 up to, but not including, https://aka.ms/OfficeSecurityReleases | https://aka.ms/OfficeSecurityReleases |
| Microsoft | Microsoft Office LTSC 2021 | 16.0.1 up to, but not including, 16.0.14334.21048 | 16.0.14334.21048 |
| Microsoft | Microsoft Office LTSC 2024 | 16.0.0 up to, but not including, 16.0.17932.21140 | 16.0.17932.21140 |
| Microsoft | 365 Apps | Not specified in the record | Not stated |
| Microsoft | Office 2021 | Not specified in the record | Not stated |
| Microsoft | Office 2024 | Not specified in the record | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- RequiredA user must take an action such as opening a file or link.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- NoneNothing can be modified.
- Availability
- NoneAvailability is not affected.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N. Scored by CNA (microsoft.com).
Official description
Product ui does not warn user of unsafe actions in Microsoft Office Outlook allows an unauthorized attacker to perform spoofing over a network.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Missing User Interaction for Potentially Unsafe Action
The product encounters a situation in which some of its behavior is security-critical and should be authorized by a human before progressing, but it does not properly consult with the human user or its proxy (such as UI approval dialogues or pre-set policies) to determine whether it is allowed to perform the potentially dangerous behavior.
How developers prevent this class of flaw
- Product systems should warn users that a potentially dangerous action may occur if the user proceeds. For example, if the user downloads a file from an unknown source and attempts to execute the file on their machine, then the application's GUI can indicate that the file is unsafe.
More Missing User Interaction for Potentially Unsafe Action vulnerabilities (CWE-356)
Timeline
- CISA published its SSVC assessment (exploitation: active, automatable: no, technical impact: partial).
- CVE record published.
- Added to CISA's Known Exploited Vulnerabilities catalogue.
- Record last changed materially (score, affected products, status or references).
- Deadline for US federal agencies to remediate, set by CISA.
References
Third-party and government advisories
- cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-124194US Government Resource
Other vulnerabilities in Microsoft 365 Apps for Enterprise
- 8.8 High severity
Recent Missing User Interaction for Potentially Unsafe Action vulnerabilities
- 7.8 High severity
- 7.8 High severity
- 8.0 High severity
- 7.0 High severity
- 7.8 High severity
- 7.0 High severity
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