Exploited CVEs / Microsoft / CVE-2023-23397
CVE-2023-23397
Microsoft Office Outlook Privilege Escalation Vulnerability. Exploitation in the wild is confirmed by CISA, not predicted. Federal agencies were required to remediate by 2023-04-04 (that deadline has passed); treat that date as the outer bound for your own environment. The fix is in the vendor advisory: Microsoft Security Update Guide (MSRC), linked below.
Actively exploited Microsoft Office vulnerability. Added to the CISA KEV catalog 2023-03-14.
Risk summary
Updated July 28, 2026. Data refreshed on every build from MSRC, CISA KEV, and FIRST EPSS.
Senserva AI Opinion for CVE-2023-23397
No macro, no link click, no attachment opening: this Microsoft Outlook flaw enables an NTLM relay in which the victim's credentials authenticate to an attacker's service, and it was exploited against targeted organizations well before its March 2023 KEV listing. Credential relay converts one poisoned message into authenticated access on other services inside the network. Microsoft rates it High Severity.
Do this: Confirm the March 2023 Outlook patch everywhere and block outbound SMB (port 445) to the internet at the perimeter.
AI-generated from public data, 2026-07-07. Verify against the vendor advisory before acting.
Senserva AI Opinion and rich prompt for CVE-2023-23397
Copy this prompt into Claude, ChatGPT, or Copilot. The facts are included, sourced from this page.
Full tracking and change history for CVE-2023-23397
Published and last-revised dates are authoritative, from Microsoft MSRC (or the CISA KEV date-added). Senserva additionally records day-to-day changes from 2026-07-07, refreshed several times a day; the change count reflects that forward-only tracking.
CISA required action
Federal (BOD 22-01) remediation due date: 2023-04-04 (past due).
Official fix for CVE-2023-23397
The authoritative fix and affected-version list are published by the vendor. Find the Office advisory on Microsoft Security Update Guide (MSRC).
Common questions about CVE-2023-23397
Is CVE-2023-23397 actively exploited?
Yes. CVE-2023-23397 was added to the CISA Known Exploited Vulnerabilities (KEV) catalog on 2023-03-14, which means exploitation in the wild has been confirmed, not predicted.
What is the CISA deadline and required action for CVE-2023-23397?
CISA set the federal (BOD 22-01) remediation due date at 2023-04-04, which has passed; treat any unremediated system as overdue.
What fixes CVE-2023-23397?
The authoritative fix is in the vendor advisory: see Microsoft Security Update Guide (MSRC) for the patched Office versions and any workarounds. KEV listing makes this a fix-first item: patch it ahead of higher-CVSS issues nobody is exploiting.
Can I ask my own AI about CVE-2023-23397?
Yes. This page includes a free, ready-to-paste AI prompt containing CVE-2023-23397's key facts: severity, CVSS, EPSS, the KEV date, the CISA due date, and the required action. Copy it into Claude, ChatGPT, or Copilot; the data is refreshed twice a day (5 AM and 3 PM US Central).
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