# CISA adds seven actively-exploited vulnerabilities to KEV catalog

Published: 2026-05-20 · Severity: high · Sectors: government-national
Canonical: https://vorant.io/reports/dbc2b638-9324-52f3-85d5-1031ca5a4bf6/cisa-adds-seven-actively-exploited-vulnerabilities-to-kev-catalog

> CISA identified seven known exploited vulnerabilities requiring federal remediation, spanning Windows, IE, Adobe, and Microsoft Defender.

CISA has added seven vulnerabilities to its Known Exploited Vulnerabilities (KEV) Catalog based on evidence of active exploitation in the wild. The catalog includes legacy Microsoft Windows and Internet Explorer flaws dating back to 2008–2010 (buffer overflows and use-after-free conditions), an Adobe Acrobat and Reader heap-based buffer overflow from 2009, and two recent Microsoft Defender vulnerabilities: an elevation of privilege flaw and a denial-of-service condition. All seven are confirmed targets of active cyber attacks. Under Binding Operational Directive BOD 22-01, Federal Civilian Executive Branch agencies are required to remediate these vulnerabilities by specified due dates; CISA urges all organizations to treat KEV Catalog entries as high-priority patches regardless of sector, as these vulnerabilities represent frequent and significant attack vectors.

## Mentioned in this report

- Vulnerabilities: CVE-2008-4250 (KEV), CVE-2009-1537 (KEV), CVE-2009-3459 (KEV), CVE-2010-0249 (KEV), CVE-2010-0806 (KEV), CVE-2026-41091 (KEV), CVE-2026-45498 (KEV)

Source reporting: https://www.cisa.gov/news-events/alerts/2026/05/20/cisa-adds-seven-known-exploited-vulnerabilities-catalog

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