What We Do
How we do it
Resources
SECURITY ADVISORIES
Oct 19, 2021
Hackers Infect Employees of Law Firms, Manufacturing Companies, and Financial Services Orgs. with Increasingly Pervasive Infostealer, SolarMarker
SolarMarker Infects 5X More Corporate Victims Using Over a Million Poisoned WordPress Pages Key Takeaways eSentire has observed a fivefold increase in SolarMarker infections. Prior to September, eSentire’s Threat Response Unit (TRU) detected and shut down one infection per week. Beginning in September, TRU averaged the detection and shutdown of five per week. SolarMarker is a…
Read More
View all Advisories →
Company
ABOUT eSENTIRE
About Us
eSentire is The Authority in Managed Detection and Response Services, protecting the critical data and applications of 1000+ organizations in 70+ countries from known and unknown cyber threats. Founded in 2001, the company’s mission is to hunt, investigate and stop cyber threats before they become business disrupting events.
Read about how we got here
Leadership Work at eSentire
LATEST PRESS RELEASE
Oct 12, 2021
eSentire Launches MDR with Microsoft Azure Sentinel Extending Response Capabilities Across Entire Microsoft Security Ecosystem
Waterloo, ON – Oct. 12, 2021 -- eSentire, recognized globally as the Authority in Managed Detection and Response (MDR), today announced the expansion of its award-winning MDR services with Microsoft Azure Sentinel, as part of its integration with the complete Microsoft 365 Defender and Azure Defender product suites supporting Microsoft SIEM, endpoint, identity, email and cloud security services.…
Read More
Partners
PARTNER PROGRAM
Partners
Our award-winning partner program offers financial rewards, sales and marketing tools and personalized training. Accelerate your business and grow your revenue by offering our world-class Managed Detection and Response (MDR) services.
Learn about our Partner Program
PARTNER RESOURCES
Apply today to partner with the Authority in Managed Detection and Response.
Login to the Partner Portal for resources and content for current partners.
Search
Resources
Security advisories — Feb 05, 2021

Chrome and Internet Explorer Zero-Day Vulnerabilities

THE THREAT

On February 4th, 2021, two separate zero-day vulnerabilities impacting the Chrome and Internet Explorer web browsers were announced.

Google confirmed a high severity vulnerability in Google Chrome that is tracked as CVE-2021-21148. The vulnerability is classified as Heap Buffer Overflow. While Google has stated there are reports of exploitation in the wild, no additional details have been provided at this time.

The South Korean cyber-security company ENKI confirmed the existence of a zero-day vulnerability affecting Internet Explorer 11, after they identified targeted attacks against their employees. The currently unnamed IE vulnerability is classified as a double-free vulnerability and has been exploited to exfiltrate victim information and deliver additional malicious content.

What we’re doing about it

What you should do about it

Additional information

CVE-2021-21148 is a heap buffer overflow vulnerability found in the V8 JavaScript engine used in the Chrome browser. Chrome updates are automatically applied to users but requires that end users close and restart Chrome.

The Internet Explorer zero-day was employed by suspected North Korean state- affiliated actors, in a previously reported campaign, targeting security researchers. The security researchers were targeted via social engineering attacks with malicious MHT/MHTML files. If the files are opened using Internet Explorer (the default application for MHT files), the user is prompted to allow script execution. If permission is given, a JavaScript payload would pull down additional malicious payloads including the IE zero-day exploit.

There is speculation that CVE-2021-21148 was exploited in this campaign. Links between exploitation of CVE-2021-21148 and this campaign have not been verified at this time.

References:

[1] https://chromereleases.googleblog.com/2021/02/stable-channel-update-for-desktop_4.html

[2] https://enki.co.kr/blog/2021/02/04/ie_0day.html

[3] https://blog.google/threat-analysis-group/new-campaign-targeting-security-researchers/