Vulnerability report

Exploitation Attempts Observed Confirmed Confidence In CISA KEV

CVE-2023-24955

Microsoft SharePoint Server Remote Code Execution Vulnerability

Microsoft SharePoint Enterprise Server 2016 · affected before 16.0.5395.1000

Watch CVE-2023-24955 Browse KEV feed
Severity
CVSS 7.2 · High
Confidence
Confirmed
Exploit status
Exploitation Attempts Observed in the Wild
EPSS
85.0%
First observed
14 Aug 2026
Last observed
10 Sep 2026

Decision summary

What security teams need to know first

Direct answers before the deeper technical record.

What it is

CVE-2023-24955 is Microsoft SharePoint Server Remote Code Execution Vulnerability.

Have exploitation attempts been observed?

Yes. Previdian sensors have observed 76 exploitation attempts, 18 unique attacker IPs, and 9 countries targeting CVE-2023-24955. First observed Aug 14, 2026; last observed Sep 10, 2026. Listed in CISA KEV. Confidence is confirmed.

Who is affected?

Affected products include Microsoft SharePoint Enterprise Server 2016 and 2 other products, including affected before 16.0.5395.1000, affected before 16.0.10398.20000, and affected before 16.0.16130.20420.

What should we do?

Patch immediately, validate internet-facing exposure, and monitor for matching requests.

Overview

Microsoft SharePoint Server Remote Code Execution Vulnerability

Microsoft SharePoint Server Remote Code Execution Vulnerability

Microsoft Affected
Microsoft SharePoint Enterprise Server 2016
Before 16.0.5395.1000
Microsoft Affected
Microsoft SharePoint Server 2019
Before 16.0.10398.20000
Microsoft Affected
Microsoft SharePoint Server Subscription Edition
Before 16.0.16130.20420
View vendor advisory (opens in new tab)
Published
09 May 2023
Exploitation Attempts Reported
26 Mar 2024
Attack vector
Remote
Complexity
Low
Privileges
High
User interaction
None

Tags

malware cisa microsoft metasploit ransomware metasploit_scanner

CVE References

Exploitation evidence

Evidence of exploitation attempts

Third-party attestation and first-party sensor observation are shown separately so teams can judge the evidence chain.

Exploitation Attempts Observed in the Wild

CISA

Recorded 26 Mar 2024

A trusted third party reported exploitation attempts.

Exploitation Attempts Observed

Previdian sensor

First observed 26 Aug 2026

Previdian sensors observed exploitation attempts targeting this vulnerability.

Targeted by Malware-Related Exploitation Attempts

CISA

Recorded 26 Mar 2024

Exploitation attempts against this vulnerability are associated with malware-related payloads.

Proof of concept available

GitHub

Recorded 28 Dec 2023

Public scanner or PoC coverage increases practical exploitability.

Known exploited vulnerability sources

Per-source evidence links for KEV attestations are available through the Previdian Pro API.

Learn about Pro API access
Source Added
CISA First 2024-03-26 00:00 UTC
Previdian Sensors 2026-08-26 12:00 UTC

Operational indicators for this CVE are listed under Detection.

Sensor telemetry

Previdian Sensor Observations

Previdian sensor observations are exploitation attempts targeting this vulnerability. They do not show that the target was vulnerable or that the attempt succeeded. The cards and chart show volume, unique attackers, and daily activity.

76

Attempts observed

18

Unique attacker IPs

9

Attacker countries

FR · HK · ID · NL · RO · RU · SA · SG · US

1

Sensors observed

CVE-2023-24955 exploitation attempts over the last 83 days

Daily events observed by Previdian sensors

Updated 14 Nov 2026

0
11
34
19
0
7
2
0
0
1
0
0
0
0
1
0
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
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0
24 Aug 10 Sep 27 Sep 14 Oct 14 Nov

First observed 14 Aug 2026 · Last observed 10 Sep 2026

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Detection

Operational artifacts and observed signals

Make the evidence actionable in scanner, SOC, and edge-control workflows.

Observed signals

Request targets
User-Agents
Callback hosts
0
0
1

Request targets and User-Agents available in Pro. Callback host details available in Enterprise.

Virtual patch status

No Previdian virtual patch is currently available. Future rules ship for ModSecurity, Cloudflare, and AWS WAF.

Learn about virtual patches →

Attacker IP Indicators

Attacker IP indicators observed · available in Pro and Enterprise.

Sensor-derived attacker IP indicators are available to Pro and Enterprise accounts under Detection and through the Pro API.

Learn about Pro API access

Scanner Artifacts

Scanner and exploit-framework references linked to this CVE.

Scanner Reference Detected
Metasploit https://github.com/rapid7/metasploit-framework/blob/master/modules/exploits/windows/http/sharepoint_dynamic_proxy_generator_auth_bypass_rce.rb 28 Apr 2025

Risk and context

Severity, weaknesses, and research context

CVSS v3.1

7.2 High

Potential damage if exploited. Separate from whether attackers are using it.

CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

EPSS

85.0%

Estimated chance of exploitation in the next 30 days. Previdian's warning comes from evidence, not this score.

Weaknesses

Improper Control of Generation of Code ('Code Injection') CWE-94

Potential Proof of Concepts

These PoCs are unverified and could contain malware. Use at your own risk.

sharepoint_dynamic_proxy_generator_auth_bypass_rce

metasploit · Created Unknown

Metasploit module for CVE-2023-24955

Timeline

From disclosure to observed exploitation attempts

  1. 11:45 UTC

    Observed by Previdian sensors

    Previdian sensors observed exploitation attempts targeting this vulnerability.

  2. 09:48 UTC

    Indicators of compromise added (19)

    Indicators of compromise recorded

  3. 15:02 UTC

    Metasploit module available

    Exploit module available

  4. 15:02 UTC

    Public PoC available

    Public proof-of-concept code published

  5. 00:00 UTC

    Added to CISA KEV

    Listed in the CISA Known Exploited Vulnerabilities catalog

  6. 00:00 UTC

    Targeted by malware-related exploitation attempts

    Malware-related exploitation attempts or payloads reported

  7. 17:03 UTC

    CVE published

    Vulnerability disclosed publicly

  8. 20:37 UTC

    CVE ID reserved

    Identifier reserved by the CNA

Pro API

Automate this intelligence

Confidence, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.

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  • Evidence confidence and provenance
  • First-party sensor telemetry
  • PoC and scanner references
  • Affected versions and enrichment
  • Automation-ready JSON delivery

GET /api/v2/pro/kevs/CVE-2023-24955

Sample API response 
{
  "cve_id": "CVE-2023-24955",
  "confidence": "Confirmed",
  "cvss_score": 7.2,
  "cvss_estimated": false,
  "epss_score": 0.84974,
  "exploit_status": {
    "exploited_in_the_wild": true,
    "active_exploitation_observed": true
  },
  "sensor_telemetry": { "attempts": 76, "sensors": 1 }
}