Active Exploitation Hits Microsoft Office RCE Flaw
CERT-FR reports over 150 Microsoft Office vulnerabilities patched in the November 2026 cycle, with CVE-2026-124194 already under active exploitation.
Sourcecert.cyber.gouv.fr — open the original
What to check
- Applies to
- The 39 CVEs named below. Whether you run an affected version is not assessed: check the versions the source lists.
- Exploitation
- CISA lists CVE-2026-124194 as exploited in the wild.
CERT-FR has published an advisory covering a large batch of Microsoft Office vulnerabilities disclosed in Microsoft's November 2026 security updates. The affected products span Microsoft 365 Apps for Enterprise (32/64-bit), Office 365 and Office LTSC for Mac, Office LTSC 2021/2024, Office Online Server, and several .NET Web ProjectTemplates packages. The flaws collectively allow remote code execution, privilege escalation, security feature bypass, and disclosure of confidential information, depending on the specific CVE and attack vector exploited.
Of particular concern, Microsoft has confirmed that CVE-2026-124194 is being actively exploited in the wild, making it the priority patch target for organizations running any of the listed Office products or versions. The advisory does not provide further technical detail on the exploitation method, targeting, or threat actor behind the activity, and CERT-FR defers to Microsoft's own bulletins for technical specifics and patch availability.
Defenders should prioritize patching CVE-2026-124194 immediately given confirmed in-the-wild exploitation, then proceed to apply the remaining fixes across all listed Office products and the .NET Web ProjectTemplates packages, referencing the official Microsoft Security Response Center bulletins linked for each CVE.
Mentioned in this report
Source reporting: https://www.cert.cyber.gouv.fr/avis/CERTFR-2026-AVI-1511
Free public brief. Slack alerts on the vendors you run come with the paid plans, and a new account gets three days of them, no card.
What this brief leaves out
This page is the free tier: the write-up, the severity, the names. In the app the same report carries live profiles of the CVEs it names. The paid plans add the security research and news reporting the free tier leaves out.
It sits in a corpus of 16,436 reports from 149 sources, 661 of them written in the last seven days, and it grows through the day.
A new account starts with three days of all of it, no card, then keeps the government and CERT reporting free. Slack alerts are a paid-plan feature: name the vendors you run and Slack hears about the reports that touch them, not the rest of the week's. Nothing is charged unless you subscribe.
Create a free account What it costs