- Critical 9.8
CVE-2026-70291
Heap-based buffer overflow in Microsoft Office Outlook allows an unauthorized attacker to execute code over a network.
Scores
The facts
- Published
- 13 October 2026
- Last changed
- 15 October 2026
- NVD status
- Analyzed
- Severity
- Critical, CVSS 9.8 out of 10 (version 3.1)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- Affects
- microsoft 365 apps
- microsoft microsoft 365
- microsoft office 2021
- microsoft office 2024
- Known exploited
- Not in the CISA Known Exploited Vulnerabilities catalogue in this build.
- EPSS
- 1.0% chance of exploitation activity in the next 30 days (percentile 62).
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