Microsoft
Microsoft Outlook zero-day exposes Windows login hashes - 2-Spyware
At a glance
Low rather than Medium: exposure is scored at a default because we cannot see your systems or suppliers. If you run or depend on Microsoft Outlook, treat it as Medium.
Briefing
- IT leaders should verify if Microsoft Outlook is in their estate and ensure systems are updated to mitigate potential risks.
Questions to ask IT
- Do we run Microsoft Outlook, and which versions?
- If it is not yet patched, what mitigation is in place, and will the fix be done by 11 Dec?
Next steps
- Confirm whether this affects systems or suppliers in your estate
- The vulnerability affects Microsoft Outlook and could lead to exposure of Windows login hashes.
Next steps
- Review the advisory against your asset inventory and patch cadence
Summary
- A zero-day vulnerability in Microsoft Outlook is reported to expose Windows login hashes, potentially affecting user account security.
- The issue involves exposure of Windows login hashes through Microsoft Outlook, with no confirmed details about active exploitation.
Products and services involved
- Microsoft Outlook98% match confidence
Part of Microsoft Outlook zero-day exposure
- A Day in the Life of a CISO: Satyam Rastogi on the decisions, people and pressures behind cybersecurity leadership
- November 2026 Patch Tuesday: 1,252 CVEs Include One Zero-Day and 68 Critical Vulnerabilities
- Exploited Outlook Zero-Day Among 1,094 Flaws Patched by Microsoft
- November Patch Tuesday boasts over 1,000 bugs but only one zero-day so far
Pulse
Last change 50m ago · Next recheck 12 Nov 2026, 12:19 UK time
- Story11 Nov 2026, 12:19 UK time · 50m ago
Linked reporting from 2-Spyware (independent original reporter).
Read source (2-Spyware)
1 entry so far. The timeline chart appears once this story has more history.
Sources
- 2-SpywareNews
Microsoft Outlook zero-day exposes Windows login hashes - 2-Spyware
How we know
Statements extracted from sources. Higher confidence means stronger corroboration.
- ClaimedHeadline60% confidence
Microsoft Outlook zero-day exposes Windows login hashes - 2-Spyware
- ProbableSummary fact75% confidence
Microsoft Outlook zero-day exposes Windows login hashes 2-Spyware The most recent protections, shipped in Firefox 145, reduce these distinguishing details so more users look alike to tracking scripts. Mozilla says this does not make fingerprinting impossible, as trackers can adapt. Firefox users should keep the browser updated to get the protections.