Buffer overflow in Microsoft Malware_protection_engine

CVE-2026-45584

Heap-based buffer overflow in Microsoft Defender allows an unauthorized attacker to execute code over a network.

Vulnerability class: Buffer Overflow

EPSS: 0.000 (9.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2026-45584?
CVE-2026-45584 is a high-severity vulnerability in Microsoft Malware_protection_engine, classified under Heap-based Buffer Overflow. CVSS score: 8.1/10. Published 2026-05-20.
How severe is CVE-2026-45584?
High severity. CVSS v3 base score is 8.1 out of 10.
Is CVE-2026-45584 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.