CISA Known Exploited Vulnerability

This vulnerability is actively exploited in the wild and listed in the CISA Known Exploited Vulnerabilities catalog.

Remediation Deadline: Jan 28, 2026

CVE-2009-0556

High

EPSS 78.2%CISA KEV

Description

Microsoft Office PowerPoint contains a code injection vulnerability that allows remote attackers to execute arbitrary code via a PowerPoint file with an OutlineTextRefAtom containing an invalid index value that triggers memory corruption.

EPSS — Exploit Probability

78.2%

Higher than 99.0% of all CVEs

Required Action

https://learn.microsoft.com/en-us/security-updates/securitybulletins/2009/ms09-017 ; https://nvd.nist.gov/vuln/detail/CVE-2009-0556

Risk Assessment

HIGH

In CISA KEV

High EPSS

Details

Severity: High
EPSS: 78.2%
CISA KEV: Yes
Ransomware: Unknown
Articles: 0

Timeline

Published

Jan 7, 2026

Added to KEV

Jan 7, 2026

Remediation Due

Jan 28, 2026

Affected Product

Microsoft

Office

View all Microsoft CVEs

External Links

NVD (NIST)CVE Details MITRE CVE