What is CVE-2021-27076?
Microsoft SharePoint Server Remote Code Execution Vulnerability
Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs low-privilege credentials, needs no user interaction, and has high impact on confidentiality, integrity, availability. 4 affected-product entries are recorded, across 1 vendor, listed below. The identifier was first published 2067 days ago.
Severity and exploitation probability
- CVSS v3.1 base score
- 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 - EPSS (FIRST)
- 14.3% probability of exploitation in the next 30 days, higher than 96.1% of all scored CVEs
- CISA KEV
- Not listed in the CISA Known Exploited Vulnerabilities catalog
- Threadlinqs priority
- 10/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- Published
- 2021-03-11, last modified 2024-11-19
Is CVE-2021-27076 being exploited?
Weaponised exploit code for CVE-2021-27076 is publicly available. 1 public proof-of-concept repository is tracked for this identifier.
- trickest/cve (trickest)
Affected products and versions
- Microsoft: SharePoint Enterprise Server 2016, SharePoint Server 2019, Business Productivity Servers 2010 Service Pack 2, SharePoint Foundation 2013 Service Pack 1
How to fix CVE-2021-27076
No vendor patch reference has been recorded for CVE-2021-27076 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.
Threat activity tracking CVE-2021-27076
4 tracked threats in the Threadlinqs corpus reference CVE-2021-27076, either in the campaign’s CVE list or as an indicator on the campaign record.
- Pro-Ukraine 'Hacking Cat' Group Deploys Gorilla RAT, Monkey Ransomware, and Nemo Wiper Against Russian Targets via Exchange/SharePoint Exploitation — HIGH · 2026-09-15
- StrikeShark Campaign: SharkLoader Dropper Targets Governments and Software Developers via N-Day Exploits and Trojanized Installers to Deploy Cobalt Strike — HIGH · 2026-07-11
- SharkLoader Malware Campaign Uses Fake Cisco AnyConnect and Google Update Installers to Deploy Cobalt Strike — HIGH · 2026-07-03
- SharkLoader Malware Deploys Cobalt Strike Beacon via DLL Side-Loading in StrikeShark Campaign — HIGH · 2026-06-27
Sources
Enriched from CVE.org, FIRST EPSS, GitHub Security Advisories, public proof-of-concept repositories. Last verified by Threadlinqs on .