What is CVE-2023-23397?

CVE-2023-23397 is a critical-severity vulnerability in Microsoft 365_apps, classified under Improper Input Validation. CVSS score: 9.8/10. Published 2023-03-14.

How severe is CVE-2023-23397?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Is CVE-2023-23397 known to be exploited?

Yes. CVE-2023-23397 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2023-03-14), indicating it is being actively exploited. 127 public proof-of-concept repositories are indexed.

Improper input validation in Microsoft 365_apps

CVE-2023-23397

Microsoft Outlook Elevation of Privilege Vulnerability

Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)

EPSS: 0.974 (99.9th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Microsoft 365_apps
Microsoft 365 Apps For Enterprise — versions 16.0.1
Microsoft Office 2019 — versions 19.0.0
Microsoft Office Ltsc 2021 — versions 16.0.1
Microsoft Outlook 2013 Service Pack 1 — versions 15.0.0.0
Microsoft Outlook 2016 — versions 16.0.0.0
Microsoft Office — versions 2019
Microsoft Office_long_term_servicing_channel — versions 2021
Microsoft Outlook — versions 2013, 2016

Weakness classification (CWE)

CISA KEV (Known Exploited Vulnerabilities)

This CVE is on the CISA KEV catalog, added on 2023-03-14. CISA KEV inclusion means CISA has confirmed in-the-wild exploitation; US federal agencies are required to remediate within a published due date.

BOD 22-01 due date: 2023-04-04.

Required action: Apply updates per vendor instructions.

Public proof-of-concept exploits

References

secure@microsoft.com (vendor-advisory, Patch, Vendor Advisory)
134c704f-9b21-4f2e-91b3-4a467353bcc0 (US Government Resource)

Frequently asked questions

What is CVE-2023-23397?: CVE-2023-23397 is a critical-severity vulnerability in Microsoft 365_apps, classified under Improper Input Validation. CVSS score: 9.8/10. Published 2023-03-14.
How severe is CVE-2023-23397?: Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2023-23397 known to be exploited?: Yes. CVE-2023-23397 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2023-03-14), indicating it is being actively exploited. 127 public proof-of-concept repositories are indexed.