cbcvebase.
CVE-2013-0074
published 2013-03-13

CVE-2013-0074: Microsoft Silverlight 5, and 5 Developer Runtime, before 5.1.20125.0 does not properly validate pointers during HTML object rendering, which allows remote…

PriorityP189high7.8CVSS 3.1
AVLACLPRNUIRSUCHIHAH
KEVITWEXPLOITRansomware
CISA Known Exploited Vulnerabilitydue 2022-06-15
Exploited in the wild
EPSS
81.87%
99.6th percentile
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."

Affected

1 ranges
VendorProductVersion rangeFixed in
microsoftsilverlight>= 5.0 < 5.1.20125.05.1.20125.0

Detection & IOCsextracted from sources · hover to see the quote

pathdata/exploits/cve-2013-0074/SilverApp1.xap
pathdata/exploits/cve-2013-0074/SilverApp1.dll
filenameSilverApp1.xap
filenameSilverApp1.dll
otherContent-Type: application/x-silverlight-2
filenameAppManifest.xaml
otherContent-Type: text/xaml
  • The exploit delivers a malicious .xap file (Silverlight application package) served with Content-Type 'application/x-silverlight-2'. Monitor HTTP responses serving this MIME type from untrusted or unexpected hosts.
  • The exploit chain uses CVE-2013-3896 (WriteableBitmap information leak) to calculate the base address of mscorlib.ni.dll before triggering CVE-2013-0074. Detecting the combined use of WritableBitmap memory disclosure followed by a dereference fault in Silverlight is a strong indicator of this exploit chain.
  • The exploit HTML page embeds a Silverlight object tag and requests a randomly named .xap file and a randomly named .dll file. Look for HTTP requests to .xap and .dll resources served from the same exploit-kit host in close temporal proximity.
  • The exploit also requests 'AppManifest.xaml' served as 'text/xaml'. An HTTP request for AppManifest.xaml from a browser process (especially Internet Explorer) is a strong indicator of Silverlight exploit-kit activity.
  • The Metasploit module targets Internet Explorer (IE6–IE10) on Windows XP SP3 / Windows 7 SP1 with Silverlight installed. Detections should focus on iexplore.exe spawning child processes or loading unexpected DLLs after fetching .xap content.
  • Post-exploitation, the Metasploit module auto-runs 'post/windows/manage/priv_migrate' to migrate the payload into a privileged process. Monitor for unexpected process migration or cross-process memory injection shortly after Silverlight content is loaded.
  • ·The exploit only targets 32-bit (x86) architecture in the newer Metasploit module variant, whereas the older exploit-db variant (29858) also targeted x86_64. Ensure detection coverage accounts for both architectures.
  • ·The .xap and .dll filenames are randomly generated (5–9 random alpha characters) per exploit session, so filename-based IOCs for these files will not be static and require pattern-based detection (e.g., random alpha string + .xap/.dll extension served as Silverlight content).
  • ·The browser requirement filter checks that the client is Internet Explorer with Silverlight enabled. Non-IE browsers or systems without Silverlight will not receive the exploit payload, limiting the attack surface.
  • ·Microsoft Silverlight is end-of-life; CISA mandates disconnection of affected systems rather than patching. Any detection strategy should prioritize identifying and removing Silverlight from the environment entirely.

CVSS provenance

nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
nvdv2.09.3CRITICALAV:N/AC:M/Au:N/C:C/I:C/A:C
vulncheck7.8HIGH
cisa7.8HIGH
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