Security readout for executives and security teams
Plain-English summary
A remote attacker could use a crafted web interaction to run malicious script in a user’s browser when using affected on-premises Dynamics 365. The victim must interact with attacker-controlled content. Successful exploitation could expose sensitive information and make limited unauthorized changes within the user’s trusted session.
Executive priority
Treat this as a high-priority browser-session compromise risk for confirmed on-premises deployments. Direct teams to establish exposure promptly and apply Microsoft’s update. Accelerate remediation where sensitive customer, operational, or identity data is accessible, while recognizing that exploitation requires a victim interaction and active exploitation is not established.
Technical view
CVE-2024-21395 is a cross-site scripting vulnerability classified as CWE-79. Its CVSS 3.1 score is 8.2: network-accessible, low complexity, no attacker privileges, user interaction required, and changed scope. The supplied vector indicates high confidentiality impact, low integrity impact, and no availability impact.
Likely exposure
Potential exposure is limited to Microsoft Dynamics 365 on-premises deployments matching the affected releases. The bundle inconsistently names product version 9.1 while listing version 9.0, so administrators should confirm applicability through Microsoft’s advisory and their installed build inventory. Cloud-hosted Dynamics products are not identified as affected by these sources.
Exploitation context
The attacker does not require prior privileges, but exploitation requires user interaction. The CVSS temporal metric reports unproven exploit maturity, and the bundle says the CVE is not in CISA KEV. These facts do not prove exploitation is absent; they mean active exploitation is not established by the supplied evidence.
Researcher notes
The affected-version data is internally inconsistent and should not be normalized without Microsoft confirmation. Analysis should follow the supplied CVSS vector rather than infer additional prerequisites or impacts. The bundle identifies a vendor patch reference but provides no update identifier, fixed build, attack examples, or telemetry demonstrating exploitation.
Mitigation direction
- Inventory on-premises Dynamics 365 instances and record exact versions and build numbers.
- Review Microsoft’s CVE advisory to resolve the supplied version inconsistency.
- Apply Microsoft’s corresponding security update according to vendor guidance.
- Prioritize internet-accessible or externally used deployments for remediation.
- Use existing web security controls as temporary risk reduction, not patch substitutes.
Validation and detection
- Confirm each instance’s edition, version, build number, and deployment model.
- Compare installed builds with Microsoft’s affected and updated version information.
- Verify the applicable Microsoft security update installed successfully.
- Retest affected web workflows using safe cross-site scripting validation methods.
- Monitor application and web security logs for suspicious script-injection activity.
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-2024-21395 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
- 8.2 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/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:N/UI:R/S:C/C:H/I:L/A:N/E:U/RL:O/RC:C2.84.7microsoftVulnerability scoring details
Base CVSS 3.1 score
8.2HighVector: CVSS:3.1/AV:N/AC:L/PR:N/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.