CVE-2016-0034VulnerabilityPublished 05/25/2022Updated 10/24/2026

CVE-2016-0034: Microsoft Silverlight Runtime Remote Code Execution Vulnerability

Affects Microsoft SilverlightSource CISA KEV

Severity

High

No CVSS score published yet

Exploitation: Actively exploited – in CISA KEV since 05/25/2022
KEV deadline: 06/15/2022
Ransomware: Used in ransomware campaigns
EPSS: 69.4% chance of exploitation in 30 days – higher than 99% of CVEs

What to do

CISA required action

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

nvd.nist.gov/vuln/detail/CVE-2016-0034 (opens in a new tab)

Description

CVE-2016-0034 is a vulnerability in Microsoft Silverlight where improper handling of negative offsets during decoding can lead to remote code execution or denial-of-service conditions. It has been exploited in the wild and is associated with known ransomware campaigns. The vulnerability is rated as high severity due to its potential impact on affected systems.

Summary

Microsoft Silverlight contains a flaw in its runtime decoding process where negative offsets are mishandled. This vulnerability allows attackers to execute arbitrary code remotely or cause a denial-of-service (DoS) condition. The issue has been observed in active exploitation scenarios, including ransomware campaigns, indicating real-world impact.

Impact

Successful exploitation of this vulnerability can result in remote code execution, allowing attackers to run arbitrary code on affected systems. Alternatively, it can cause denial-of-service conditions, disrupting normal operation. The presence of known exploits in the wild and ransomware use underscores the critical risk posed by this vulnerability.

Mitigation

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Since no patch links or official remediation details are provided, users should consult Microsoft’s security advisories for Silverlight to determine if updates or mitigations are available. Until then, consider disabling Silverlight if not required.

Weaknesses

CWE-20Improper Input Validation (opens in a new tab)

What to do

Description

AnalysisAI-generated, updated 10/24/2026, 11:50:44 UTC

Weaknesses

References

Related threats