Original release date: June 30, 2022

CISA, the Federal Bureau of Investigation (FBI), the Department of the Treasury (Treasury), and the Financial Crimes Enforcement Network (FinCEN) have released a joint Cybersecurity Advisory (CSA), #StopRansomware: MedusaLocker, to provide information on MedusaLocker ransomware. MedusaLocker actors target vulnerabilities in Remote Desktop Protocol (RDP) to access victims’ networks. Note: this joint #StopRansomware CSA is part of an ongoing #StopRansomware effort to publish advisories for network defenders that detail various ransomware variants and ransomware threat actors.

CISA, FBI, Treasury and FinCEN encourage network defenders to examine their current cybersecurity posture and apply the recommended mitigations in this joint CSA, which include:

• Prioritize remediating known exploited vulnerabilities.
• Train users to recognize and report phishing attempts.
• Enable and enforce multifactor authentication.

See #StopRansomware: MedusaLocker to learn about MedusaLocker actors’ tactics, techniques, and procedures and the recommended mitigations. Additionally, review the U.S. government resource StopRansomware.gov for more guidance on ransomware protection, detection, and response. 

Original release date: June 28, 2022

 CISA has released guidance on switching from Basic Authentication (“Basic Auth”) in Microsoft Exchange Online to Modern Authentication (“Modern Auth”) before Microsoft begins permanently disabling Basic Auth on October 1, 2022. Basic Auth is a legacy authentication method that does not support multifactor authentication (MFA), which is a requirement for Federal Civilian Executive Branch (FCEB) agencies per Executive Order 14028, “Improving the Nation’s Cybersecurity”. Although this guidance is tailored to FCEB agencies, CISA urges all organizations to switch to Modern Auth before October 1 and enable MFA. 
 
CISA recommends all organizations review Switch to Modern Authentication in Exchange Online Before Basic Authentication Deprecation and prioritize moving to Modern Auth. For more information, CISA recommends reviewing Microsoft’s Deprecation of Basic Authentication in Exchange Online documentation and the associated Exchange Team blog post, Basic Authentication Deprecation in Exchange Online.

Original release date: June 27, 2022

CISA has added eight new vulnerabilities to its Known Exploited Vulnerabilities Catalog, based on evidence of active exploitation. These types of vulnerabilities are a frequent attack vector for malicious cyber actors and pose significant risk to the federal enterprise. Note: to view the newly added vulnerabilities in the catalog, click on the arrow in the “Date Added to Catalog” column, which will sort by descending dates.     

Binding Operational Directive (BOD) 22-01: Reducing the Significant Risk of Known Exploited Vulnerabilities established the Known Exploited Vulnerabilities Catalog as a living list of known CVEs that carry significant risk to the federal enterprise. BOD 22-01 requires FCEB agencies to remediate identified vulnerabilities by the due date to protect FCEB networks against active threats. See the BOD 22-01 Fact Sheet for more information.

Although BOD 22-01 only applies to FCEB agencies, CISA strongly urges all organizations to reduce their exposure to cyberattacks by prioritizing timely remediation of Catalog vulnerabilities as part of their vulnerability management practice. CISA will continue to add vulnerabilities to the Catalog that meet the specified criteria.     

Original release date: June 23, 2022

 CISA and the United States Coast Guard Cyber Command (CGCYBER) have released a joint Cybersecurity Advisory (CSA) to warn network defenders that cyber threat actors, including state-sponsored advanced persistent threat (APT) actors, have continued to exploit CVE-2021-44228 (Log4Shell) in VMware Horizon® and Unified Access Gateway (UAG) servers to obtain initial access to organizations that did not apply available patches. The CSA provides information—including tactics, techniques, and procedures and indicators of compromise—derived from two related incident response engagements and malware analysis of samples discovered on the victims’ networks.

CISA and CGCYBER encourage users and administrators to update all affected VMware Horizon and UAG systems to the latest versions. If updates or workarounds were not promptly applied following VMware’s release of updates for Log4Shell, treat all affected VMware systems as compromised. See joint CSA Malicious Cyber Actors Continue to Exploit Log4Shell in VMware Horizon Systems for more information and additional recommendations.
 

Original release date: June 22, 2022

CISA is aware that Forescout researchers have released OT:ICEFALL, a report on 56 vulnerabilities caused by insecure-by-design practices in operational technology across multiple vendors. The vulnerabilities are divided into four main categories: insecure engineering protocols, weak cryptography or broken authentication schemes, insecure firmware updates and remote code execution via native functionality.

CISA has released five corresponding Industrial Controls Systems Advisories (ICSAs) currently to provide notice of the reported vulnerabilities and identify baseline mitigations for reducing risks to these and other cybersecurity attacks.  

CISA encourages users and administrators to review the OT:ICEFALL report as well as the following ICSAs for technical details and mitigations.

• ICSA-22-172-02 : JTEKT TOYOPUC
• ICSA-22-172-03 : Phoenix Contact Classic Line Controllers
• ICSA-22-172-04 : Phoenix Contact ProConOS and MULTIPROG
• ICSA-22-172-05 : Phoenix Contact Classic Line Industrial Controllers
• ICSA-22-172-06 : Siemens WinCC OA