Red Hot Cyber
Cybersecurity, Cybercrime News and Vulnerability Analysis

CVE-2026-45659

View the latest critical CVEs issued
This is a free service offered by Red Hot Cyber to the community. It allows you to view, on a single page, information about a single CVE from the National Vulnerability Database (NVD) and the National Institute of Standards and Technology (NIST) of the United States of America, the Forum of Incident Response and Security Teams (FIRST) regarding the EPSS score and percentile, data from the KEV catalog of the Cybersecurity and Infrastructure Security Agency (CISA), as well as selected resources from Red Hot Cyber and other international sources.

National Vulnerability Database Information

Description: Deserialization of untrusted data in Microsoft Office SharePoint allows an authorized attacker to execute code over a network.

CVSS Base Score: 8.8 (v3.1)

The CVSS Base Score is a score from 0 to 10 that represents the intrinsic severity of a vulnerability. A higher score indicates greater severity.

Value
0.02.55.07.510.0
Published on: 05/22/2026 23:16:56
Last modified: 07/23/2026 11:10:00
NIST: CVE source from the National Vulnerability Database (NVD)

CVSS Metrics Details

  • Base Severity: HIGH
  • Vector String: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
  • Attack Vector: NETWORK
  • Attack Complexity: LOW
  • Privileges Required: LOW
  • User Interaction: NONE
  • Scope: UNCHANGED
  • Confidentiality Impact: HIGH
  • Integrity Impact: HIGH
  • Availability Impact: HIGH

Common Weakness Enumeration (CWE)

Database CWE: v4.18

CWE-502: Deserialization of Untrusted Data ↗

The product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.

Fonte: MITRE CWE


FIRST Information

EPSS Score: 0.0912

The EPSS (Exploit Prediction Scoring System) is a score from 0 to 1 that indicates the probability that a vulnerability will be exploited in the real world in the next 30 days. A higher value indicates a greater likelihood of exploitation.

Value
0.00.250.50.751.0

Percentile: 0.9479

The Percentile indicates how much higher this vulnerability's EPSS score is compared to all other vulnerabilities in the EPSS database. For example, a percentile of 0.90 (90%) means that 90% of vulnerabilities have an EPSS score equal to or lower than the current one.

Value
0.00.250.50.751.0

*Data updated as of: 2026-08-01


CISA Information (Known Exploited Vulnerabilities)

The CISA KEV Catalog lists vulnerabilities that have been actively exploited in the real world. If a CVE is present in this catalog, it indicates that the threat is immediate and mitigation should be a top priority.

CVE CVE-2026-45659 IS PRESENT in the CISA KEV Catalog!

  • Vulnerability Name: Microsoft SharePoint Server Deserialization of Untrusted Data Vulnerability
  • Short Description: Microsoft SharePoint Server contains a deserialization of untrusted data vulnerability which allows an authorized attacker to execute code over a network.
  • Date Added to KEV: 07/01/2026
  • Vendor/Product: Microsoft / SharePoint Server
  • Required Action: Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
  • Due Date: 07/04/2026


Exploit PoC from GitHub