Microsoft Security Response Center

Microsoft mitigates China-based threat actor Storm-0558 targeting of customer email

Tuesday, July 11, 2023

UPDATE: Microsoft performed a comprehensive technical investigation into the acquisition of the Microsoft account consumer signing key, including how it was used to access enterprise email. Our technical investigation has concluded, and on September 6, 2023, we published our investigation findings. Microsoft has released threat analysis on Storm-0558 activity here. Microsoft additionally released additional defense-in-depth security fixes to help customers improve token validation in their custom applications.

Breaking Barriers: Aditi’s Journey Through Sight Loss to Microsoft AI Innovator

Wednesday, June 28, 2023

Facts about Aditi Shah: Tools she uses: Aditi’s main tool is JAWS, a screen reader from Freedom Scientific, which she touts as the best in the market. This tool has made her digital life more manageable, enabling her to perform almost any task independently. Aditi also uses Seeing AI, a Microsoft app that she uses for important life tasks, like reading her mail, providing descriptions of different products, identifying colors for her outfits, and more.

Potential Risk of Privilege Escalation in Azure AD Applications

Tuesday, June 20, 2023

Summary Microsoft has developed mitigations for an insecure anti-pattern used in Azure AD (AAD) applications highlighted by Descope, and reported to Microsoft, where use of the email claim from access tokens for authorization can lead to an escalation of privilege. An attacker can falsify the email claim in tokens issued to applications.

Azure AD

Microsoft Response to Layer 7 Distributed Denial of Service (DDoS) Attacks

Friday, June 16, 2023

Summary Beginning in early June 2023, Microsoft identified surges in traffic against some services that temporarily impacted availability. Microsoft promptly opened an investigation and subsequently began tracking ongoing DDoS activity by the threat actor that Microsoft tracks as Storm-1359. These attacks likely rely on access to multiple virtual private servers (VPS) in conjunction with rented cloud infrastructure, open proxies, and DDoS tools.

Microsoft mitigates set of cross-site scripting (XSS) vulnerabilities in Azure Bastion and Azure Container Registry

Wednesday, June 14, 2023

Summary Microsoft recently mitigated a set of cross-site scripting vulnerabilities affecting Azure Bastion and Azure Container Registry (ACR). Exploitation of these vulnerabilities could have potentially allowed for an unauthorized user to gain access to a target user’s session within the compromised Azure service, and subsequently lead to data tampering or resource modification.

Hey Yara, find some vulnerabilities

Thursday, June 08, 2023

Intro Finding vulnerabilities in software is no easy task by itself. Doing this at cloud scale is very challenging to perform manually, and we use tools to help us identify patterns or vulnerability signatures. Yara is one of those tools. Yara is a very popular tool with Blue teams, malware researchers, and for good reason.

Announcing The BlueHat Podcast: Listen and Subscribe Now!

Wednesday, May 17, 2023

Available today on all major podcast platforms is The BlueHat Podcast, a new series of security research focused conversations, continuing the themes from the BlueHat 2023 conference (session recordings available to watch here). Since 2005, BlueHat has been where the security research community, and Microsoft, come together as peers: to debate, discuss, share, challenge, celebrate and learn.

BlueHat

Guidance related to Secure Boot Manager changes associated with CVE-2023-24932

Tuesday, May 09, 2023

Summary Today, Microsoft is releasing CVE-2023-24932, and associated configuration guidance, to address a Secure Boot bypass vulnerability used by the BlackLotus bootkit to exploit CVE-2022-21894. Customers will need to closely follow the configuration guidance to fully protect against this vulnerability. This vulnerability allows an attacker to execute self-signed code at the Unified Extensible Firmware Interface (UEFI) level while Secure Boot is enabled.

Microsoft Vulnerability Severity Classification for Online Services Publication

Tuesday, April 18, 2023

The Microsoft Security Response Center (MSRC) is always looking for ways to provide clarity and transparency around how we assess the impact of vulnerabilities reported in our products and services. We have published a new Microsoft Vulnerability Severity Classification for Online Services to provide additional information about our approach to online services and web applications.

Congratulations to the Top MSRC 2023 Q1 Security Researchers!

Thursday, April 13, 2023

Congratulations to all the researchers recognized in this quarter’s Microsoft Researcher Recognition Program leaderboard! Thank you to everyone for your hard work and continued partnership to secure customers. The top three researchers of the 2023 Q1 Security Researcher Leaderboard are: Kai Lu (@K3vinLuSec), Yuki Chen, and wh1tc & Edwardzpeng! Check out the full list of researchers recognized this quarter here.

Microsoft Security Response Center Blog