AEGLIX vulnerability intelligence
CVE-2026-21509
HIGH · CVSS 7.8 · Analyzed
Published: 2026-01-26 · Updated: 2026-06-25 · Source: NVD
Vulnerability overview
Reliance on untrusted inputs in a security decision in Microsoft Office allows an unauthorized attacker to bypass a security feature locally.
Severity and scoring
- CVSS score
- 7.8 · HIGH
- CVSS version
- 3.1
- CVSS vector
- CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- Weaknesses
- CWE-807
CVSS measures technical severity; it does not establish whether this vulnerability is being exploited in your environment.
Known exploitation and remediation
Listed in CISA’s Known Exploited Vulnerabilities catalog.
- Affected product
- Microsoft · Office
- Added to catalog
- 2026-01-26
- Required action
- Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
- CISA remediation due date
- 2026-02-16
CISA deadlines apply to the organizations covered by its directives. Confirm your own remediation requirements.
Verify affected versions and patch availability in the vendor advisory before making changes.
Affected products and versions
cpe:2.3:a:microsoft:365_apps:-:*:*:*:enterprise:*:x64:*
cpe:2.3:a:microsoft:365_apps:-:*:*:*:enterprise:*:x86:*
cpe:2.3:a:microsoft:office:2016:*:*:*:*:*:x64:*
cpe:2.3:a:microsoft:office:2016:*:*:*:*:*:x86:*
cpe:2.3:a:microsoft:office:2019:*:*:*:*:*:x64:*
cpe:2.3:a:microsoft:office:2019:*:*:*:*:*:x86:*
cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:*:*:*:*:-:x64:*
cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:*:*:*:*:-:x86:*
cpe:2.3:a:microsoft:office_long_term_servicing_channel:2024:*:*:*:*:-:x64:*
cpe:2.3:a:microsoft:office_long_term_servicing_channel:2024:*:*:*:*:-:x86:*
These are NVD CPE applicability entries. Some products depend on configuration conditions; consult the official record to confirm applicability.
Advisories and references
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21509
Vendor Advisory
- https://www.vicarius.io/vsociety/posts/cve-2026-21509-detection-script-microsoft-office-security-feature-bypass-vulnerability
Third Party Advisory
- https://www.vicarius.io/vsociety/posts/cve-2026-21509-mitigation-script-microsoft-office-security-feature-bypass-vulnerability
Mitigation · Third Party Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-21509
US Government Resource