JASBUG is a security bug disclosed in February 2015 and affecting core components of the Microsoft Windows Operating System. The vulnerability dated back to 2000[1] and affected all supported editions of Windows Server 2003, Windows Vista, Windows Server 2008, Windows 7, Windows Server 2008 R2, Windows 8, Windows Server 2012, Windows RT, Windows 8.1, Windows Server 2012 R2, and Windows RT 8.1.[2]

CVE identifier(s)CVE-2015-0008
Date discoveredJanuary 2014; 8 years ago (2014-01)
DiscovererJeff Schmidt (JAS Global Advisors)
Affected softwareMicrosoft Windows workstations and servers on an Active Directory domain (from Windows Server 2003 to Windows 8.1)

The vulnerability allows hackers to remotely take control of Windows devices that connect to an Active Directory domain.[3]

JASBUG is registered in the Common Vulnerabilities and Exposures system as CVE-2015-0008.[4][5] The Industrial Control Systems Cyber Emergency Response Team, part of the Department of Homeland Security, issued ICS-ALERT-15-041-01,[6] warning control systems owners that they should expedite applying critical JASBUG fixes.

Microsoft released two patches, MS15-011 and MS15-014,[7] to address JASBUG on the same day the vulnerability was disclosed. These fixes took Microsoft over a year to develop and deploy[8] due to the complexity of the JASBUG vulnerability.

At the time of disclosure, more than 300 million computers were believed to be vulnerable to the exploit.[9]


JASBUG was disclosed to the public by Microsoft as a part of "Patch Tuesday," on February 10th, 2015.[10]


The vulnerability was initially reported to Microsoft in January 2014[11] by Jeff Schmidt, founder of JAS Global Advisors.[12] After Microsoft publicly announced the security vulnerability, it garnered the name JASBUG in reference to the role JAS Global Advisors played in discovering the exploit.[13]


In 2014, JAS Global Advisors was working on an engagement with the Internet Corporation for Assigned Names and Numbers (ICANN), the organization governing the standards of the Internet, to research potential technical issues surrounding the rollout of new Generic Top Level Domains (gTLDs) on the Internet.[14]

While working on the research, JAS Global Advisors, with business partner SimMachines,[15] uncovered the vulnerability by applying "big data" analytical techniques to very large technical data sets.


JASBUG principally affects business and government users. Home users are less likely to be affected by JASBUG because they do not use domain-configured computers.[16]

White House cybersecurity advisor Michael Daniel spoke about the importance of addressing JASBUG in a meeting of the Information Security and Privacy Advisory Board of the National Institute for Standards and Technology, and the Office of Management and Budget and the Department of Homeland Security immediately took steps to fix the vulnerability on federal networks.[17]

Suzanne E. Spaulding, serving as Under Secretary for the National Protection and Programs Directorate (NPPD) at the Department of Homeland Security, mentioned JASBUG in a February 2015 House of Representatives hearing that touched on the potential effect of a DHS funding hiatus.[18]

In the aftermath of JASBUG, various government agencies have updated their technical specifications to mitigate exploit risks. For example, the United States Department of Veteran Affairs decided in May 2015 to "unapprove" the use of Windows Server 2003 based on JASBUG risks.[19]


According to Microsoft, the exploit takes advantage of how Group Policy receives and applies policy data when a domain-joined system connects to a domain controller.[20] One likely exploitation of the flaw involves deceiving a user with a domain-configured system into a network controlled by a hacker.[21]

Despite the potential effect, there is no indication that the JASBUG vulnerability was ever used by cyberhackers to access corporate or government computers.[22]

Specific systems affectedEdit

JASBUG affects Windows Vista, Windows Server 2008, Windows 7, Windows Server 2008 R2, Windows 8, Windows 8.1, Windows Server 2012, Windows Server 2012 R2, Windows RT, and Windows RT 8.1.[23] Windows Server 2003 is also affected, but there will not be a JASBUG patch this platform, as Microsoft has indicated that it is not feasible to build a fix for this version. [24] JASBUG also affects Windows XP and Windows 2000, but no patch will be made available for these operating systems as they are no longer supported by Microsoft.[25]

Bugfix and deploymentEdit

Unlike other high-profile vulnerabilities like Heartbleed, Shellshock, Gotofail and POODLE, JASBUG was a design problem, not an implementation problem, making this type of vulnerability unusual and much more difficult to fix.[26] The fix required Microsoft to re-engineer core components of the operating system[27] and to add several new features, including additional hardening of Group Policy, the feature that organizations use to centrally manage Windows systems, applications, and user settings in Active Directory environments.[28]

Microsoft was not able to fix the JASBUG flaw on Windows Server 2003 systems, noting that "The architecture to properly support the fix provided in the update does not exist on Windows Server 2003 systems, making it infeasible to build the fix for Windows Server 2003."[29]

For unpatched and unpatchable platforms that may be vulnerable to JASBUG, security firms like Symantec recommend that organizations use intrusion prevention systems (IPS) to monitor network activity for possible malicious JASBUG traffic.[30]


  1. ^ Pagliery, Jose (2015-02-15). "Microsoft fixes a serious 15-year-old bug". CNN Money. Retrieved 2015-02-15. If any hackers knew about this since the year 2000, they could have used it to sneak into company computer systems and take complete control.
  2. ^ Walker, Danielle (2015-02-10). "On Patch Tuesday, Microsoft unveils fix for critical Windows flaw 'JASBUG'". SC Magazine. Retrieved 2015-03-10. In a security bulletin, MS15-011, the tech giant revealed that the critical vulnerability affects all supported editions of Windows Server 2003, Windows Vista, Windows Server 2008, Windows 7, Windows Server 2008 R2, Windows 8, Windows Server 2012, Windows RT, Windows 8.1, Windows Server 2012 R2, and Windows RT 8.1.
  3. ^ Williams, Owen (2015-02-10). "Microsoft Patches Massive Flaw In Active Directory". The Next Web. Retrieved 2015-03-10. Today, Microsoft has issued a critical patch to every supported version of Windows that resolves a bug that may have been open for as long as fifteen years could allow attackers to remotely take control of Windows devices that connect to an Active Directory domain.
  4. ^ "CVE - CVE-2015-0008". Cve.mitre.org. 2015-02-10. Retrieved 2015-03-10.
  5. ^ Thomson, Iain (2015-02-10). "PATCH NOW: Design flaw in Windows security allows hackers to own corporate laptops, PCs". The Register. Retrieved 2015-03-10. The bug (CVE-2015-0008) was discovered over a year ago when global DNS overlord ICANN hired JAS to check out the security of its systems for creating new generic top-level domains. {{cite news}}: External link in |quote= (help)
  6. ^ "Alert (ICS-ALERT-15-041-01) Microsoft Security Bulletin MS15-011 JASBUG". US-CERT. 2015-02-10. Retrieved 2015-03-10. Control systems that are members of a corporate Active Directory may be at risk. ICS-CERT is monitoring this vulnerability and will provide additional information related to control systems as it becomes available.
  7. ^ "MS15-011 & MS15-014: Hardening Group Policy". Microsoft. 2015-02-10. Retrieved 2015-03-10.
  8. ^ Saarinen, Juha (2015-02-10). "Microsoft patches critical JASBUG Windows flaw". ITNews Australia. Retrieved 2015-03-10. In order to remedy the flaw, Microsoft was forced to re-engineer core components of Windows, to add several new features. This meant extensive testing to ensure backwards compatibility, supported configurations, and new documentation to describe the changes was required, a process that took Microsoft over a year.
  9. ^ Gaebler, Ken (2015-02-10). "New JASBUG Vulnerability Escalates The Importance Of Applying Today's Microsoft Patches". Gaebler Resources for Entrepreneurs. Retrieved 2015-03-10. Outside of the Fortune 500, we estimate that another 300 million computers could be affected by the JASBUG security threat.
  10. ^ Hamilton, David (2015-02-10). "Microsoft Issues Security Updates Addressing'JASBUG' Vulnerability in Windows". Web Host Industry Review. Retrieved 2015-03-10. Microsoft released technical patches [for JASBUG] as a part of its "Patch Tuesday" release on 10 February 2015.
  11. ^ Fox-Brewster, Thomas (2015-02-10). "Why Microsoft Took A Year To Fix Critical Windows Bug That Allowed Hackers To Spy On Worker PCs". Forbes. Retrieved 2015-03-10. ...the Redmond tech titan learned about the problem back in January 2014.
  12. ^ Chickowski, Ericka (2015-02-11). "Microsoft Fix For Critical Active Directory Bug A Year In The Making". Dark Reading. Retrieved 2015-03-10. Discovered by Jeff Schmidt, founder of JAS Global Advisors, the flaw required Microsoft to fix to fix how domain-configured systems connect to domain controllers.
  13. ^ "Jasbug: Microsoft plugs 15 year old Vulnerability". Der Spiegel. 2015-02-11. Retrieved 2015-03-10. Das Sicherheitsleck wurde nach einer der Firmen benannt, die es Microsoft gemeldet haben. Weil das Unternehmen JAS Global Advisors heißt, heißt die Lücke Jasbug.
  14. ^ Zaharov-Reutt, Alex (2015-02-10). "Critical "JASBUG" vulnerability in Windows clients and servers patched". IT Wire. Retrieved 2015-03-10.
  15. ^ Prince, Brian (2015-02-10). "Microsoft Patches Critical Windows, Internet Explorer Vulnerabilities in Patch Tuesday Update". Security Week. Retrieved 2015-03-10.
  16. ^ Kumar, Mohit (2015-02-10). "15-Year-Old JasBug Vulnerability Affects All Versions of Microsoft Windows". Hacker News, The. Retrieved 2015-03-10. Jasbug vulnerability do [sic] not affects home users because they are not usually domain-configured
  17. ^ Mazmanian, Adam (2015-02-11). "Feds respond to critical Windows flaw". Federal Computer Week. Retrieved 2015-03-10.
  18. ^ "Examining The President's Cybersecurity Information-Sharing Proposal". United States House of Representatives Hearing. 2015-02-25. Retrieved 2015-03-10. That has an impact on our ability to quickly address--identify and address vulnerabilities like the JASBUG vulnerability that has been most recently in the media.
  19. ^ "Windows Server". US Department of Veteran Affairs Website. 2015-05-31. Retrieved 2015-03-10. Due to the critical nature of JASBUG, Windows Server 2003 is TRM unapproved and should only be used when the security risks are outweighed by the benefits as reviewed and approved by the AERB waiver process.
  20. ^ "Microsoft Security Bulletin MS15-011 - Critical". Microsoft TechNet. 2015-02-10. Retrieved 2015-03-10.
  21. ^ Illascu, Inotu (2015-02-11). "Microsoft Patches Critical Remote Code Execution Glitch in Group Policy". Softpedia. Retrieved 2015-03-10.
  22. ^ "Microsoft fixes critical remotely exploitable Windows root-level design bug". Help Net Security. 2015-02-10. Retrieved 2015-03-10. ...there is no indication that it had been publicly used to attack customers.
  23. ^ "New Windows JASBUG vulnerability requires immediate attention from systems administrators". Symantec. 2015-02-11. Retrieved 2015-03-10.
  24. ^ Goodin, Dan (2015-02-10). "15-year-old bug allows malicious code execution in all versions of Windows". Ars Technica. Retrieved 2015-03-10. Patch now, unless you run 2003, in which case you're out of luck.
  25. ^ Duval, Loic (2015-02-12). "JASBUG, le bug âgé de 14 ans qui fait peur aux entreprises". Tom's Hardware. Retrieved 2015-03-10. Les versions Windows 2000 et XP n’étant plus supportées par Microsoft, il n’existe pas de correctifs.
  26. ^ Wilhelm Aldershoff, Jan (2015-02-10). "BREAKING: Microsoft fixes very critical vulnerability called JASBUG; bigger than Heartbleed and Shellshock". MyCE. Retrieved 2015-03-10.
  27. ^ Freed, Anthony M. (2015-02-10). "Microsoft Updates Core Windows Components to Patch Critical JASBUG Vulnerability". Dark Matters. Retrieved 2015-03-10. In a rare move, Microsoft had to re-engineer some core components of the Windows operating system in order to mitigate a critical design vulnerability that could allow attackers to gain administrator-level privileges on tens-of-millions of devices.[permanent dead link]
  28. ^ Constantin, Lucian (2015-02-11). "Critical vulnerability in Group Policy puts Windows computers at risk". CSO Magazine. Retrieved 2015-03-10.
  29. ^ Bott, Ed (2015-02-10). "Microsoft's Patch Tuesday release leaves one big vulnerability unpatched". ZDNet. Retrieved 2015-03-10.
  30. ^ "JASBUG: What is it? How Are You Protecting Your Legacy Windows Systems?". Symantec. 2015-02-17. Retrieved 2015-03-10.