Microsoft Word Preview Pane Use-After-Free Remote Code Execution
CVE-2026-40361 is a critical use-after-free vulnerability in Microsoft Word. The provided content consistently describes it as a memory-safety flaw in Word that can trigger code execution when a specially crafted Word document is opened or merely previewed. Multiple sources in the content state that this vulnerability is exploitable through the Preview Pane, meaning the target may not need to explicitly open the malicious document for exploitation to occur. Microsoft assessed this issue as 'Exploitation More Likely' within 30 days of release, and the content lists a CVSS score of 8.4.
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Impact
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Mitigation
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Remediation
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Exploits
No public exploits tracked yet. Mallory keeps watching.
No public exploit code observed for this vulnerability.
Affected products & vendors
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Recent activity
31 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.
A Microsoft Word remote code execution vulnerability caused by use-after-free that can be exploited via the Preview Pane without requiring the user to open the file.
A use-after-free vulnerability in Microsoft Word that can trigger code execution when a crafted document is opened or previewed.
A critical Microsoft Word remote code execution vulnerability that can be triggered through the Preview Pane without opening the document, making user interaction requirements minimal.
A Microsoft Word remote code execution vulnerability exploitable via the Preview Pane and assessed by Microsoft as more likely to be exploited within 30 days.
The version that knows your environment.
Query your assets running an affected version, and investigate the blast radius.
Every observed campaign linking this CVE to a named adversary.
Malware families riding this exploit, with evidence and IOCs.
YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.
Cross-references every affected SKU, including bundled OEM variants.
Community discussion across Reddit, Mastodon, and other social sources.