Security readout for executives and security teams
Plain-English summary
CVE-2021-1713 is a high-severity Microsoft Excel remote code execution vulnerability. A successful attack could let code run when a user interacts with a malicious Excel-related file or content. The provided sources show user interaction is required and do not show active exploitation.
Executive priority
Prioritize this as a normal high-severity Microsoft Office remediation item. It can affect confidentiality, integrity, and availability, but the provided evidence does not support emergency treatment for active exploitation.
Technical view
The vulnerability affects multiple Microsoft Excel, Office, Microsoft 365 Apps for Enterprise, Office Online Server, and Office Web Apps Server versions. CVSS 3.1 is 7.8 with local attack vector, low complexity, no privileges required, user interaction required, and high confidentiality, integrity, and availability impact.
Likely exposure
Exposure is most likely where affected Office or Excel versions remain installed, especially Office 2010 SP2, 2013 SP1, 2016, 2019, Microsoft 365 Apps for Enterprise, Office Online Server, or Office Web Apps Server 2013.
Exploitation context
The source bundle marks CISA KEV as false and CVSS exploit maturity as unproven. Treat exploitation as plausible because impact is high, but there is no supplied evidence of active exploitation or public weaponization.
Researcher notes
The key constraints are CVSS AV:L and UI:R, meaning exploitation depends on local/user-assisted document handling. The bundle does not include CWE details, root cause specifics, proof-of-concept status, or exact fixed build numbers.
Mitigation direction
- Review the Microsoft MSRC advisory for product-specific update guidance.
- Apply Microsoft security updates for every affected Office, Excel, and server product.
- Prioritize externally used document workflows and shared Office server deployments.
- Verify older Office versions are either updated or removed from production use.
- Until updated, reduce handling of untrusted Excel files where operationally possible.
Validation and detection
- Inventory endpoints and servers for the affected Microsoft products and versions.
- Confirm installed Office, Excel, Office Online Server, and Web Apps Server patch levels.
- Check vulnerability scanners for CVE-2021-1713 coverage and current detections.
- Review EDR or email security telemetry for suspicious Office document execution.
- Document exceptions where affected products cannot be promptly updated.
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.
Execution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2021-1713 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
- 7.8 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/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.
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:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C1.85.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
7.8HighVector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
Source materials
- CVE List V5 sourceCVE List V5
- Microsoft Excel Remote Code Execution VulnerabilityCVE reference · vendor-advisory
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-1713CVE reference · x_refsource_MISC, x_transferred
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.