Actively exploitedKnown ransomware use

CVE-2013-0074 Microsoft Silverlight Double Dereference Vulnerability

Microsoft Silverlight does not properly validate pointers during HTML object rendering, which allows remote attackers to execute code via a crafted Silverlight application.

From the CISA KEV catalogue version 2026.11.06, with Cybergen analysis. Updated 6 Nov 2026.

Our Assessment

Should You Worry?

Patch nowCybergen assessment
  • CISA confirmed exploitation in the wild and added it to the Known Exploited Vulnerabilities catalogue on 25 May 2022.
  • CISA lists it as known to be used in ransomware campaigns.
  • Rated High severity (CVSS 7.8, scored by CISA).
  • It has been in the catalogue for 1,626 days. Systems still unpatched now have almost certainly been scanned for it.
The Vulnerability

What It Is

Microsoft Silverlight 5, and 5 Developer Runtime, before 5.1.20125.0 does not properly validate pointers during HTML object rendering, which allows remote attackers to execute arbitrary code via a crafted Silverlight application, aka "Silverlight Double Dereference Vulnerability."

From Watch to Action

What To Do Now

  1. 1

    Find it

    Search your asset inventory and external attack surface for Microsoft Silverlight. Include cloud images, appliances and anything a supplier runs for you.

    Attack Surface Management
  2. 2

    Fix it

    The impacted product is end-of-life and should be disconnected if still in use.

    Vulnerability Management
  3. 3

    Hunt for compromise

    If an affected system was reachable before you patched, assume it may have been hit. Check logs, new accounts, web shells and outbound connections from the date of exposure.

    Incident Response
  4. 4

    Prove it is fixed

    Rescan or test the system after patching. Upgrades that fail silently and forgotten secondary instances are common.

    Penetration Testing

Not Sure If You Are Exposed?

Our attack surface and vulnerability teams can check your internet-facing estate for CVE-2013-0074 and every other exploited flaw on the list.

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