Critical CVSS 8.6 EPSS 0.03703 2020-09 archive

Executive Summary

A remote code execution vulnerability exists in Microsoft SharePoint Server when it fails to properly identify and filter unsafe ASP.Net web controls. An authenticated attacker who successfully exploited the vulnerability could use a specially crafted page to perform actions in the security context of the SharePoint application pool process. To exploit the vulnerability, an authenticated user must create and invoke a specially crafted page on an affected version of Microsoft SharePoint Server. The security update addresses the vulnerability by correcting how Microsoft SharePoint Server handles processing of created content.

Overview

8.6
CVSS HIGH
Critical
MS Severity
Not Exploited
MS Exploit Status
Less Likely
MS Exploit Likelihood
Category Remote Code Execution
Released Sep 8 2020
Last Updated Sep 8 2020
Publicly Disclosed No
CISA KEV Not Listed
Known Exploits None Known
EPSS Score 0.03703 — 0.88318 percentile
NVD CVSS 8.6 HIGH — matches MSRC

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:L/E:P/RL:O/RC:C
ATTACK VECTOR
Network
ATTACK COMPLEXITY
Low
PRIVILEGES REQUIRED
None
USER INTERACTION
None
SCOPE
Unchanged
CONFIDENTIALITY
Low
INTEGRITY
High
AVAILABILITY
Low
EXPLOIT CODE MATURITY
Proof-of-Concept
REMEDIATION LEVEL
Official Fix
REPORT CONFIDENCE
Confirmed
Temporal Score: 7.7

EPSS Score

0.03703
probability of exploitation in the next 30 days
0.88318 percentile - updated 2026-06-21
View on FIRST.org

Affected Products

5 affected products
Product KB Article Severity Impact Restart Required
Microsoft SharePoint Enterprise Server 2013 Service Pack 1 4484515 (Security Update) Critical Remote Code Execution Maybe
Microsoft SharePoint Enterprise Server 2016 4484506 (Security Update) Critical Remote Code Execution Maybe
Microsoft SharePoint Foundation 2010 Service Pack 2 4486667 (Security Update) Critical Remote Code Execution Maybe
Microsoft SharePoint Foundation 2013 Service Pack 1 4484488 (Security Update) Critical Remote Code Execution Maybe
Microsoft SharePoint Server 2019 4484505 (Security Update) Critical Remote Code Execution Maybe

Patches

5 patches
Article Type Restart
4484515 Security Update Maybe
4484506 Security Update Maybe
4486667 Security Update Maybe
4484488 Security Update Maybe
4484505 Security Update Maybe

Known Exploits

Acknowledgments

Oleksandr Mirosh (@olekmirosh) from Micro Focus Fortify