CRITICALCVSS 9.1Actively exploited · CISA KEV since 2026-08-18Vulnerability
CVE-2026-55040
Microsoft SharePoint contains a weak authentication vulnerability which allows an unauthorized attacker to bypass a security feature over a network.
Properties
- Euvd product
- Microsoft SharePoint Enterprise Server 2016, Microsoft SharePoint Server Subscription Edition, Microsoft SharePoint Server 2019
- Vulnerability name
- Microsoft SharePoint Weak Authentication Vulnerability
- First seen
- 2026-10-08T18:16:58+00:00
- Cvss score
- 9.1
- Epss score
- 0.69536
- Last seen
- 2026-10-19T12:00:27+00:00
- Due date
- 2026-08-21
- Euvd assigner
- microsoft
- Retrieved at
- 2026-10-21T01:24:49+00:00
- Exploited euvd since
- 2026-08-18T00:00:00+00:00
- Src batch id
- epss_history-20261020T103617Z-728ddd
- Source url
- https://epss.empiricalsecurity.com/epss_scores-2026-10-19.csv.gz
- Date added
- 2026-08-18
- Euvd base score version
- 3.1
- Score
- 9.1
- Fetched at
- 2026-10-20T10:36:20+00:00
- Euvd vendor
- Microsoft
- Cvss vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
- In Signal since
- initial import (Sep 2026)
- Euvd base score
- 9.1
Related Entities (6)
AFFECTS_PRODUCT (3)
DESCRIBES (1)
HAS_WEAKNESS (1)
INVOLVES (1)
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