CVE-2023-23396
Published: 14 March 2023
Summary
CVE-2023-23396 is a medium-severity Uncontrolled Resource Consumption (CWE-400) vulnerability in Microsoft Office Online Server. Its CVSS base score is 6.5 (Medium).
Operationally, ranked in the top 4.4% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.
Deeper analysis
Microsoft Excel contains a denial of service vulnerability tracked as CVE-2023-23396 and assigned CWE-400. The flaw affects the Microsoft Excel application and carries a CVSS 3.1 base score of 6.5 reflecting network attack vector, low attack complexity, no required privileges, and required user interaction, resulting in high impact to availability while leaving confidentiality and integrity untouched.
An unauthenticated remote attacker can supply a specially crafted Excel file or link that, once opened by a victim, triggers the denial-of-service condition and renders the application unavailable. No code execution or data compromise is indicated by the provided scoring details.
Microsoft has published remediation guidance for CVE-2023-23396 on its Security Response Center site, directing administrators to the corresponding security update for affected Excel versions. The associated EPSS score has remained flat at 0.1970 with no material increase since disclosure.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2023-27496
Vulnerability details
Microsoft Excel Denial of Service Vulnerability
- CWE(s)
Related Threats
No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.
Affected Assets
Mitigating Controls
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Limiting concurrent sessions directly prevents uncontrolled resource consumption by capping the number of active sessions per user or account.
Analysis identifies uncontrolled resource consumption indicative of denial-of-service or abuse attempts.
Contingency plan testing includes resource exhaustion scenarios to verify recovery, making it harder for attackers to sustain exploits that cause uncontrolled consumption.
Updated contingency plans include current procedures to detect, contain, and recover from resource exhaustion, limiting an attacker's ability to sustain impact from uncontrolled consumption.
Alternate site allows resumption of operations if resource exhaustion at the primary site is exploited to cause unavailability.
Alternate telecommunications services enable resumption of essential functions when primary services become unavailable due to uncontrolled resource consumption.
The team can analyze and respond to resource exhaustion incidents, reducing the impact of attacks that exploit uncontrolled consumption weaknesses.
Timely maintenance support and spare parts enable rapid recovery from failures induced by uncontrolled resource consumption, shortening the impact window of denial-of-service attacks.