Security readout for executives and security teams
Plain-English summary
This is a high-severity cross-site scripting flaw in Microsoft Dynamics 365 on-premises. A low-privileged attacker could target a user and potentially expose sensitive information or make limited unauthorized changes. Successful exploitation requires user interaction; the supplied evidence does not show active exploitation.
Executive priority
Treat this as a high-priority remediation, especially where Dynamics 365 contains sensitive customer or business data. It is not supported as an active-exploitation emergency by the supplied evidence, but its confidentiality impact and low attack complexity justify prompt patch verification.
Technical view
CVE-2024-21393 is CWE-79 with CVSS 3.1 score 7.6. The vector indicates network access, low complexity, low privileges, user interaction, and changed security scope. Potential impact is high confidentiality loss and low integrity loss, with no indicated availability impact.
Likely exposure
Exposure is limited to affected Microsoft Dynamics 365 on-premises deployments. The bundle identifies version 9.1 but separately lists 9.0, creating ambiguity. Confirm exact affected builds against Microsoft’s advisory and inventory any externally accessible or broadly used instances.
Exploitation context
An attacker requires low privileges and must persuade a user to interact with malicious content. The CVSS temporal metric marks exploit maturity as unproven, and the CVE is not listed as KEV in the supplied bundle. This does not prove exploitation has never occurred.
Researcher notes
The changed-scope vector and high confidentiality impact make session or sensitive-data exposure important assessment concerns, but the bundle provides no vulnerable parameter, attack path, indicators, or patch identifier. Avoid assuming affected builds from the inconsistent version fields; use Microsoft’s advisory as the applicability authority.
Mitigation direction
- Review Microsoft’s update guide for affected builds and the applicable security update.
- Apply the vendor-provided update using normal change-control and backup procedures.
- Prioritize internet-accessible or heavily used Dynamics 365 on-premises instances.
- Restrict unnecessary access while remediation is pending.
- Review Microsoft guidance for any additional mitigations or prerequisites.
Validation and detection
- Inventory Dynamics 365 on-premises versions, builds, and exposure paths.
- Resolve the 9.0 versus 9.1 version ambiguity using Microsoft’s advisory.
- Confirm the applicable security update is installed on every affected instance.
- Verify update status through deployment records and authenticated build checks.
- Review security monitoring for suspicious user-supplied web content or unexpected browser behavior.
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-2024-21393 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
- High
- CVSS
- 7.6 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:L/A:N/E:U/RL:O/RC:C
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.
SSVC decision data
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:H/I:L/A:N/E:U/RL:O/RC:C2.34.7microsoftVulnerability scoring details
Base CVSS 3.1 score
7.6HighVector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:L/A:N/E:U/RL:O/RC:C
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- Microsoft Dynamics 365 (on-premises) Cross-site Scripting VulnerabilityCVE reference, microsoft · vendor-advisory, patch
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.