Dark Reading is part of the Informa Tech Division of Informa PLC

This site is operated by a business or businesses owned by Informa PLC and all copyright resides with them.Informa PLC's registered office is 5 Howick Place, London SW1P 1WG. Registered in England and Wales. Number 8860726.


06:10 PM

Microsoft Concludes Internal Investigation into Solorigate Breach

The software giant found no evidence that attackers gained extensive access to services or customer data.

Microsoft, which calls the SolarWinds supply chain attack a "moment of reckoning," declared on Thursday it had completed an internal investigation of its own compromised network. It advises companies to strengthen security by adopting a zero trust mindset and protecting privileged credentials.

While the breach, which Microsoft calls "Solorigate", allowed sophisticated attackers to view source code for some of its products, Microsoft stressed that its investigators concluded neither the company's services nor its software had been used to attack others.

The closing of this investigation comes less than two months after Microsoft revealed that attackers had viewed some of the source code for its products and services. In a separate statement on Feb. 18, the Microsoft Security Response Center (MSRC) disclosed the attackers viewed specific source code repositories looking for passwords and development "secrets" used as keys to secure applications once compiled.

Microsoft's investigation found that only "a small number of [code] repositories" were accessed by the intruders, including a small subset of Azure, Intune, and Exchange components.

"The search terms used by the actor indicate the expected focus on attempting to find secrets," the MSRC states in its blog post, adding that company policy prohibits any passwords or code-signing secrets in code. Microsoft automates verification of this policy, but double-checked the code during incident response. "We have confirmed that the repositories complied and did not contain any live, production credentials," officials write.

Vasu Jakkal, corporate vice president for security, compliance, and identity at Microsoft, noted the fact that security companies and large software firms were clearly targeted by the attackers should worry the industry and customers.

Related Content:

7 Things We Know So Far About the SolarWinds Attacks

Special Report: Understanding Your Cyber Attackers

New From The Edge: Breach Etiquette: How to Mind Your Manners When It Matters

"Today, as we close our own internal investigation of the incident, we continue to see an urgent opportunity for defenders everywhere to unify and protect the world in a more concerted way," she writes. "We also see an opportunity for every company to adopt a Zero Trust plan to help defend against future attacks."

The speed with which Microsoft wrapped its investigation caused some security professionals to question the company's thoroughness. Incident responders are in the tough position of having to declare a negative — that attackers did not gain significant access, says Joe Slowik, senior threat researcher with network infrastructure firm DomainTools.

"It does seem like this didn't take very long for them to finish up, given the length of time compared to the potential level of access that the attackers were able to achieve in the victims' networks," he says. "Microsoft saying that [the attackers] didn't get access — full stop — seems very fast."

While acknowledging that Microsoft is in a better position to make such declarations, compared to most of the industry, Slowik questioned the wisdom in declaring the investigation over. 

Microsoft focused much of its conclusions on advising companies that two measures could make them more secure: Adopting a zero trust mindset and protecting the privileged accounts that attackers strive to compromise. While these have long been recommendations for IT security teams, especially as companies move to distributed workforces linked with cloud based services, Microsoft stressed that sophisticated attackers will target access and credentials. 

"The cybersecurity industry has long been aware that sophisticated and well-funded actors were theoretically capable of advanced techniques, patience, and operating below the radar, but this incident has proven that it isn't just theoretical," the MSRC writes in its conclusions. "For us, the attacks have reinforced two key learnings that we want to emphasize — embracing a zero trust mindset and protecting privileged credentials."

Industry professionals criticized Microsoft's touting of cloud services as self-serving but lauded the company's focus on adopting a zero trust architecture.

"The adoption of a zero trust architecture was something that had already been accelerating in light of the pandemic and the new normal of working from home," Oliver Tavakoli, chief technology officer at Vectra. "Microsoft points out that organizations should go one step further by adopting it as a 'mindset' [and] accept that all of the initial lines of defense can fail and that security controls need to be layered across all systems critical to an organization."

DomainTools' Slowik argued that companies should focus on gaining visibility into their trust relationships. While "zero trust" has become overused in cybersecurity firms' marketing, he says, the essence of the recommendations are valid.

"Zero trust is a problematic concept — more a buzzword than truly useful — but it does highlight a trend that adversaries are increasingly able and willing to abuse trust relationships," Slowik says. "The upshot for defenders and network owners is that we need to better at monitoring, defending, and controlling those trust relationships."

Veteran technology journalist of more than 20 years. Former research engineer. Written for more than two dozen publications, including CNET News.com, Dark Reading, MIT's Technology Review, Popular Science, and Wired News. Five awards for journalism, including Best Deadline ... View Full Bio

Recommended Reading:

Comment  | 
Print  | 
More Insights
Newest First  |  Oldest First  |  Threaded View
Inside the Ransomware Campaigns Targeting Exchange Servers
Kelly Sheridan, Staff Editor, Dark Reading,  4/2/2021
Beyond MITRE ATT&CK: The Case for a New Cyber Kill Chain
Rik Turner, Principal Analyst, Infrastructure Solutions, Omdia,  3/30/2021
Register for Dark Reading Newsletters
White Papers
Current Issue
2021 Top Enterprise IT Trends
We've identified the key trends that are poised to impact the IT landscape in 2021. Find out why they're important and how they will affect you today!
Flash Poll
How Enterprises are Developing Secure Applications
How Enterprises are Developing Secure Applications
Recent breaches of third-party apps are driving many organizations to think harder about the security of their off-the-shelf software as they continue to move left in secure software development practices.
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
PUBLISHED: 2021-04-14
Nextcloud Desktop Client prior to 3.1.3 is vulnerable to resource injection by way of missing validation of URLs, allowing a malicious server to execute remote commands. User interaction is needed for exploitation.
PUBLISHED: 2021-04-14
Appspace 6.2.4 is vulnerable to stored cross-site scripting (XSS) in multiple parameters within /medianet/sgcontentset.aspx.
PUBLISHED: 2021-04-14
A Insecure Temporary File vulnerability in s390-tools of SUSE Linux Enterprise Server 12-SP5, SUSE Linux Enterprise Server 15-SP2 allows local attackers to prevent VM live migrations This issue affects: SUSE Linux Enterprise Server 12-SP5 s390-tools versions prior to 2.1.0-18.29.1. SUSE Linux Enterp...
PUBLISHED: 2021-04-14
A stack-based buffer overflow vulnerability has been reported to affect QNAP NAS devices running Surveillance Station. If exploited, this vulnerability allows attackers to execute arbitrary code. QNAP have already fixed this vulnerability in the following versions: Surveillance Station (an...
PUBLISHED: 2021-04-14
In the standard library in Rust before 1.50.3, there is an optimization for joining strings that can cause uninitialized bytes to be exposed (or the program to crash) if the borrowed string changes after its length is checked.