Applied Cybernetics Group
Threat intel → detection pipeline
Friday, September 18, 2026
Data as of 13:09 UTC

known ransomware use

Microsoft Silverlight Runtime Remote Code Execution Vulnerability

Added to KEV
2022-05-25
Federal due date
2022-06-15
Vendor
Microsoft
Product
Silverlight
EPSS
99.3th percentile (score 0.696, as of 2026-09-16)
NVD CVSS v3.1
8.8 (HIGH)
Ransomware use
Known
Upstream
https://nvd.nist.gov/vuln/detail/CVE-2016-0034

CISA short description

Microsoft Silverlight mishandles negative offsets during decoding, which allows attackers to execute remote code or cause a denial-of-service (DoS).

Required action

The impacted products are end-of-life and should be disconnected if still in use.

NVD description

Microsoft Silverlight 5 before 5.1.41212.0 mishandles negative offsets during decoding, which allows remote attackers to execute arbitrary code or cause a denial of service (object-header corruption) via a crafted web site, aka "Silverlight Runtime Remote Code Execution Vulnerability."

EPSS percentile is the FIRST.org exploit-probability ranking as of the date noted above; it moves daily. CVSS reflects NVD's analysis at time of publication.