CVE-2026-45659
Microsoft SharePoint Remote Code Execution Vulnerability
CVE-2026-45659 is a high vulnerability (CVSS 8.8) in Microsoft Sharepoint Enterprise Server 2016, published May 22, 2026. CISA lists it as known to be exploited, since July 1, 2026. EUVD reports exploitation since July 1, 2026. Public exploit code exists. EPSS puts the chance of exploitation in the next 30 days at 80.2%, the 99th percentile. No source names a fixed version.
- Severity
- 8.8 HighCVSS 3.1, CVE List
- Exploit chance
- 80.2%EPSS, 99th percentile
- Exploitation
- ExploitedCISA KEV,
- Fixed in
- No fix listedNo source names one
Description
Deserialization of untrusted data in Microsoft Office SharePoint allows an authorized attacker to execute code over a network.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
Discussion
Affected products
Public exploits
Links only. Every CVE stores no exploit code.
| Source | Link | Date |
|---|---|---|
| PoC in GitHub | HORKimhab/CVE-2026-45659 | 2026-05-27 |
What each source reports
CVE List Score used
Microsoft SharePoint Remote Code Execution Vulnerability
Deserialization of untrusted data in Microsoft Office SharePoint allows an authorized attacker to execute code over a network.
- Record
CVE-2026-45659- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C - Weakness
- CWE-502
- Updated
- 2026-11-02
EUVDEUVD-2026-31518
Deserialization of untrusted data in Microsoft Office SharePoint allows an authorized attacker to execute code over a network.
- Record
EUVD-2026-31518- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-w3mh-jmwv-56f3
Deserialization of untrusted data in Microsoft Office SharePoint allows an authorized attacker to...
Deserialization of untrusted data in Microsoft Office SharePoint allows an authorized attacker to execute code over a network.
- Record
GHSA-w3mh-jmwv-56f3- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-502
- Updated
- 2026-11-02
CISA KEVNo score
Microsoft SharePoint Server Deserialization of Untrusted Data Vulnerability
Microsoft SharePoint Server contains a deserialization of untrusted data vulnerability which allows an authorized attacker to execute code over a network.
- Record
CVE-2026-45659- Weakness
- CWE-502
- Updated
- 2026-11-02
NVD
Deserialization of untrusted data in Microsoft Office SharePoint allows an authorized attacker to execute code over a network.
- Record
CVE-2026-45659- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-502
- Updated
- 2026-11-02
History
| Recorded | Changed | Sources |
|---|---|---|
| exploitation | ||
| first indexed | CVE List, EUVD, GitHub Advisories, CISA KEV, NVD, PoC in GitHub |
Dates are when Every CVE recorded each change. Upstream dates may differ.