Security readout for executives and security teams
Plain-English summary
A crafted web request to SharePoint can trigger cross-site scripting because input was not properly sanitized. An attacker needs some privileges and a victim interaction, so this is not a mass unauthenticated server takeover, but it can still affect browser-session data and user trust.
Executive priority
Handle through the normal vulnerability remediation cycle, with higher priority for internet-facing SharePoint. The business risk is moderate because exploitation needs privileges and user interaction, but SharePoint often hosts sensitive collaboration content.
Technical view
CVE-2020-0893 is a CWE-79 XSS in Microsoft SharePoint Enterprise Server 2016 and 2013 SP1, and SharePoint Server 2019. CVSS 3.1 is 5.4: network reachable, low complexity, low privileges required, user interaction required, changed scope, low confidentiality and integrity impact, no availability impact.
Likely exposure
Exposure is most likely in organizations running affected on-premises SharePoint versions, especially externally reachable portals or collaboration sites with broad user access. The provided sources do not identify SharePoint Online or other Microsoft products as affected.
Exploitation context
The source bundle does not show CISA KEV listing or cited evidence of active exploitation. Exploitation requires a specially crafted web request, low privileges, and user interaction, limiting urgency compared with unauthenticated remote code execution.
Researcher notes
Key constraints are PR:L and UI:R, with changed scope and low confidentiality/integrity impact. The public bundle does not provide proof-of-concept details, active exploitation evidence, or exact remediation package details, so validation should stay tied to Microsoft guidance.
Mitigation direction
- Review Microsoft's CVE-2020-0893 advisory for applicable SharePoint security updates.
- Patch affected SharePoint 2013 SP1, 2016 Enterprise, and 2019 deployments per vendor guidance.
- Prioritize externally accessible or partner-facing SharePoint sites.
- Restrict SharePoint access to trusted users where business requirements allow.
- Monitor vendor guidance for superseding updates or additional mitigations.
Validation and detection
- Inventory SharePoint Server and SharePoint Enterprise Server versions in use.
- Confirm whether any affected versions remain reachable internally or externally.
- Check patch management records against Microsoft advisory guidance for CVE-2020-0893.
- Review web logs for suspicious requests to SharePoint around user-facing pages.
- Verify no remediation assumptions are made beyond vendor-published guidance.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-79: User-session and phishing behavior lookup
Client-side and session-facing weaknesses should be reviewed alongside initial-access and user-execution behaviors. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2020-0893 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 5.4 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N2.32.7Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
5.4MediumVector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
Source materials
- CVE List V5 sourceCVE List V5
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-0893CVE reference · x_refsource_MISC
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.