IOC Radar
CVEMediumSignal 54/100EPSS 13.9%

CVE-2026-21509

First Seen
Jun 2, 2026
Last Seen
Jun 3, 2026
Jun 2
First Seen
4d ago
Jun 3
Last Seen
3d ago
2
Reports
source reports
72%
Confidence
medium
Found in 2 reports. Confidence: medium. · Confidence scores are heuristic. Verify before acting on results.
CVE
Known vulnerability being actively exploited in the wild.
MISP Category
vulnerability
EPSS Score
13.87%
EPSS Percentile
94.4th
Confidence
72%
Signal Score
54 / 100
IDS Rule
No
CVE Intelligence
Exploit Probability13.87%
94.4th percentile of all CVEs
Threat Context
Threat Actors1
AAPT28
Tags

Feed Intelligence Summary

2 reports72% confidence
RF
Recorded Future Blog
Feb 24, 2026
January 2026 CVE Landscape: 23 Critical Vulnerabilities Mark 5% Increase, APT28 Exploits Microsoft Office Zero-Day
30 IOCs in report
SS
Synaptic Systems
Feb 3, 2026
APT28: Geofencing as a Targeting Signal (CVE-2026-21509 Campaign)
6 IOCs in report

Activity Timeline

2 total obs
Feb 24Feb 3

Threat Activity Heatmap

· Peak: 2026-02-03
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24h
0
Dormant
7d
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3mo
0
Dormant
Threat ScoreMedium Risk
54
SIGNAL
Signal Score
72%
Confidence
2
Reports
First seenJun 2, 2026
Last seenJun 3, 2026

VirusTotal

Not checked

Export & API

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IOC Journey

medium
First detected 4 days ago · Last seen 3 days ago
Appeared in 2 threat reports from 2 sources
Associated with: APT28